• 한국수소및신에너지학회논문집
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• 제6권1호
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• pp.17-22
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• 1995

Thermally evaporated Pd films on substrate were hydrogenated upto 1 bar of hydrogen gas at room temperature. Temperature dependence hange of electrical resistivity on Pd films is examined in the thickness range between $60{\AA}$ and $990{\AA}$. Resistivity of Pd is fitted well with Bloch-$Gr{\ddot{u}}neisen$ formula. Debye temperatures of Pd films are about 254 K, which are 20 K lower than that of bulk Pd. Debye temperature is not sensitive to film thickness change. Temperature of substrate during evaporation changes temperature dependence of resistivity of films much. Optical phonon contribution increases with decreasing temperature of PdHx.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.383-388
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• 2003

This study investigates the change of the temperature and mechanical properties of the braking disk for the railway vehicle. The average temperature is measured about $100^{\circ}C$ and the maximum temperature is measured over $200^{\circ}C$ by non-contact sensor from Seoul to Chunan. In the $20^{\circ}C-300^{\circ}C$, the $0.2\%$ offset yield strengths of the disk (GC25-30 material) are a little down to the reference value, but the linear relation of tensile test result is not find from the linear change of temperature. However, $J_{IC}$ values have the inverse proportion to the temperature, and the $J_{IC}$ value at $200^{\circ}C$ decrease $30.55\%$ from the $J_{IC}$. value of the room temperature. This result means that the crack length on the braking disk is rapidly increase at $200^{\circ}C$

• 수산경영론집
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• 제47권4호
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• pp.31-44
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• 2016

The purpose of this study is to analyze the climate change exposure of fisheries and fish species in the southern sea of Korea under the RCP climate change scenarios. The extent of exposure was calculated through weighted sum of the sea temperature forecasted by National Institute of Fisheries Science, and the weight were obtained from the time-space distribution of each fisheries or species, based on the micro-data for the fishing information reported by each fisherman. Results show that all the exposed sea temperature of RCP8.5 is higher than that of RCP4.5 in year 2100 as well as in near 2030, therefore it is thought to be very important to reduce the GHG emission even in the short term. The extent of exposure was analyzed to be comparatively high especially in the fisheries such as anchovy drag nets and species like cod, anchovy and squid. Meanwhile the method of this study is considered to be excellent to obtain the accurate extent of exposure under RCP scenarios, and therefore it is applicable on assessing the vulnerability of climate change in fisheries.

• 한국축산시설환경학회지
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• 제20권2호
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• pp.49-56
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• 2014

The climate of the earth is expected to change rapidly and continuously. Despite climate change is expected to impact on productivity of crop and livestock, a study for adaptation and impact of livestock to global warming is not enough. This study was performed to develop a method to evaluate the effects of heat stress on dairy cattle. Feedlot environment and health status of livestock were measured through an infrared thermography camera and a temperature-humidity sensor. Environmental factors such as temperature and humidity were measured to calculate the Temperature humidity index (THI). The change of the milk yield was similar to THI data pattern, suggesting that THI might play an important role to predict the effect of climate change on dairy cattle. THI data would be useful to predict long-term climate change effects on dairy cattle with RCP8.5 scenario.

• 설비공학논문집
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• 제17권2호
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• pp.125-130
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• 2005

This study was peformed to investigate the phase change temperature, the supercooling, the maintenance time of liquid phase and the change rate of volume of TMA 30 $wt\% clathrate compound with additives. TMA 30 $wt\% clathrate compound with additive was cooled at heat source temperature of $-6^{circ}C$. The additives are ethylene glycol and chloroform. Their concentration are 0.1$wt\% respectively. The experimental results showed that the phase change temperature was not affected by additives and this was average $5.3^{circ}C$. Also the supercooling and the maintenance time of liquid phase were decreased by additives. Especially, the average value of supercooling showed by $8.8^{circ}C$ and the maintenance time of liquid phase was by 19 minutes in the case of chloroform 0.1$wt\%. Additionally, the average change rate of volume showed by $1.26{\~}1.31\%$ according to additives and the volume was decreased by the phase change from liquid to solid.

• 대기
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• 제34권2호
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• pp.123-138
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• 2024

Using 18 multi-model-based a Shared Socioeconomic Pathway (SSP) and Representative Concentration Pathways (RCP) climate change scenarios, future changes in temperature and warmth index on the Korean Peninsula in the 21st century (2011~2100) were analyzed. In the analysis of the current climate (1981~2010), the ensemble averaged model results were found to reproduce the observed average values and spatial patterns of temperature and warmth index similarly well. In the future climate projections, temperature and warmth index are expected to rise in the 21st century compared to the current climate. They go further into the future and the higher carbon scenario (SSP5-8.5), the larger the increase. In the 21st century, in the low-carbon scenario (SSP1-2.6), temperature and warmth index are expected to rise by about 2.5℃ and 24.6%, respectively, compared to the present, while in the high-carbon scenario, they are expected to rise by about 6.2℃ and 63.9%, respectively. It was analyzed that reducing carbon emissions could contribute to reducing the increase in temperature and warmth index. The increase in the warmth index due to climate change can be positively analyzed to indicate that the effective heat required for plant growth on the Korean Peninsula will be stably secured. However, it is necessary to comprehensively consider negative aspects such as changes in growth conditions during the plant growth period, increase in extreme weather such as abnormally high temperatures, and decrease in plant diversity. This study can be used as basic scientific information for adapting to climate change and preparing response measures.

• 대한기계학회논문집
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• 제14권2호
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• pp.422-429
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• 1990

The experimental study investigates two aspects of counterflow sensible heat regenerator operation. First, it examines the regenerator performance in periodic steady state operation with spatially nonuniform inlet temperature in one of the fluid stream. Second, the study examines the transient response of a regenerator to a step change in the inlet temperature of one of the fluid streams. The effect of transient inlet temperatures is analyzed in terms of the response of the outlet fluid temperatures to a step change in temperature of one of the inlet fluid streams. The effect of temperature nonuniformities is analyzed in terms of the change of temperature nonuniformities is analyzed in terms of the change in steady state effectiveness due to a circumferential temperature distribution in one of the inlet fluid streams. an experimental analysis has been conducted using a counterflow, parallel passage, and rotary regenerator made from polyethylene film. Efficiencies follow similar trends with increasing matrix to fluid capacity rate ratio for the balanced and symmetric regenerator with nonuniform inlet temperature.

• 대한가정학회지
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• 제29권1호
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• pp.13-25
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• 1991

We measured change of peripheral skin temperature and mean skin temperature when the upper arm and thigh are pressured in order to know the effect of skin pressure applied by clothing on blood circulation. After release from pressure, we observed also recovery condition. At the same time, we examined relation between pressure and a feeling of thightness. Three physiques of healthy females, namely slender, standard and plump, served as subjects. We used continuous restraint method with skin pressure applied by experimental fabric for 10 min. As a result of this experiment, we obtained following findings. 1. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under upper arm restraint. The peripheral and mean skin temperature decreased with the lapse of restraint time. A remarkable tendency observed according to the increase of restraint pressure. Recovery condition after release from pressure not yet recovered to original state, for all after a lapse of 10 min. 2. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under thigh restraint, especially different physique was remarkable among them. The peripheral skin temperature decreased or decreased. Recovery condition after release from pressure was the same upper arm. 3. Main factor affecting the evaluation of a feeling of tightness was restraint pressure. The value of pressure sensation made remarkable declined after a lapse of 10 min restraint time. Individual differences, however, were shown in pressure sensation.

• 전기학회논문지
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• 제60권3호
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• pp.669-673
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• 2011

This study explores the numerical analysis method of fluid dynamics in the reaction section to improve the gas processing efficiency in the hazardous gas removal by atmospheric thermal plasma. This study also intends to contribute in technology advance to improve the processing efficiency and make the process more stable. Numerical analysis of temperature distribution in the reaction section dependent on the change in flow velocity of Ar and plasma temperature change, which are major control variables in the cracking process of HFC-23 using arc plasma, was done. The characteristic of incoming oxygen by temperature suggested that when temperature increased to 1600K, 1700K, 1800K respectively, the range of cracking temperature 1500K increased to 75.0%, 83.3%, 90.2% respectively. The temperature change of Ar by velocity change was widest in the area higher than 1500K when the velocity was 2.5m/s; however, since there was no big difference when the velocity was 2m/s, it is believed that 2 m/s would be most proper.

• 생태와환경
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• 제55권4호
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• pp.341-351
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• 2022

The physiological characteristics, growth, and yield of each regional rice variety ('Odaebyeo', 'Saechucheong', 'Ilmibyeo') were investigated depending on the impact of changes in temperature and CO₂ concentration. Experiments were conducted with a control group, which reflected atmospheric CO₂ concentration and temperature, and treatment groups, in which the CO₂ concentration and temperature were increased by 250 ppm and 2.0℃ from those in the control group. The results showed that the increase in CO₂ concentration and temperature reduced the growth and yield of the rice 'Odaebyeo', but did not substantially change the productivity of the 'Saechucheong' and 'Ilmibyeo'. The increase in CO₂ concentration and temperature increased stomatal conductance and rate of transpiration of the 'Odaebyeo' variety, thereby decreasing its water use efficiency (WUE). In contrast, the increase in CO₂ concentration and temperature increased the photosynthetic rate and WUE of the 'Saechucheong' and 'Ilmibyeo' varieties. The gradual change in climate is considered to directly affect growth and development of rice and diversely affect the productivity of each variety. Therefore, it is necessary to implement technological development, select regionally optimal rice varieties, develop new rice varieties, as well as conduct long-term monitoring of each rice variety for climate adaptation to counter global warming.