• 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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.84-87
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• 2001

Space charge formation at high temperature was investigated in several polymers using pulsed electro-acoustic (PEA) method. In SXLPE, homocharge is found and increased as an increase of temperature. In a charge of polarity of poling voltage(positive to negative), space charge mainly cause of hole injection. In Ionomer, heterocharge is found because of ion. As an increase of temperature heterocharge is also increased. In PET, As an increase of temperature homocharge is decreased.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.168-168
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• 2022

According to the 5th Climate Change Report, global average temperature in 2081~2100 will increase 1.8℃ based on RCP 4.5 and 3.7℃ based on RCP 8.5 from the current climate value (IPCC Working Group I AR5). As temperature is expected to increase due to global warming and the intensity and frequency of rainfall are expected to increase, damage to crops is expected, and countermeasures must be taken. This study intends to evaluate rice growth in terms of nitrogen utilization efficiency according to future climate change conditions. In this experiment, Oryza sativa cv. Shindongjin were planted at the SPAR facility of the NICS in Wanju-gun, Jeollabuk-do on June 10, and were planted and grown according to the standard cultivation method. Cultivation conditions are high temperature, high CO₂ (current temperature+4.7℃·CO₂ 800ppm), high temperature (current temperature+4.7℃·CO₂ 400ppm), current climate (current tempreture·CO₂ 400 ppm). Nitrogen was varied as 0, 9, 18 kg/10a. The N content and C/N ratio of all rice leaves, stems, and seeds increased at high temperature, and the N content and C/N ratio decreased under high temperature and high CO₂ conditions com pared to high temperature. Compared to the current climate, NUE increases by about 8% under high temperature and high CO₂ conditions and by about 2% under high temperature conditions. This seems to be because the increase in temperature and CO₂ induced the increase in biomass. ANUE related to yield decreased by about 70% compared to the current climate under high temperature conditions, and decreased by about 45% at high temperature and high CO₂, showing a tendency to decrease compared to high temperature. This appears to be due to reduced fertility and poor ripening due to high temperature stress. However, as the nitrogen increased, the number of ears and the number of grains increased, slightly offsetting the production reduction factor.

• Journal of Environmental Impact Assessment
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• v.19 no.2
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• pp.169-177
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• 2010

One of the most obvious climatic manifestations of urbanization in Korea is a trend towards higher air temperature. The trends of long-term annual temperature generally well describe the warming of urban areas. The increase of air temperature in urban area has been observed to the present since the meteorological observations in Korea began. The objective of this study is to explore the actual increase and the regional long-term trends of air temperature attributed to urbanization in the Korean Peninsula. Therefore, temperatures of the selected urban areas were compared with that of the surrounding rural areas, with the results varying by the application of the estimates of each region. The second objective is to separate the long-term trend of surface air temperature of global warming from urbanization and to find the actual temperature increase from urbanization in Korean peninsula. For the data analysis, daily air temperatures observed by the Korea Meteorological Administration (KMA) during between from 1961 and 2005 were used at five rural sites and cities. The re-analyzed surface air temperatures by the National Centers for Environmental Prediction (NCEP) was also carried out to compare the result from the observed air temperature in the Korean climate domain. In this study, the urban areas in Korea showed high increase rate of air temperature with $0.4^{\circ}C$ per decade during past 50 year period, while rural sites as Chupungryung with the $0.2^{\circ}C$ decadal increase rate. The analyses reflect that the urban area shows the high rate of temperature increase with $1.39^{\circ}C$ of regression value at the urban area, Seoul, and $0.43^{\circ}C$ at the rural site, Chupungnyeong during the period of 30 years. The temperature increas due to the urbanization only showed the increase range between $0.44^{\circ}C$ and $0.86^{\circ}C$, and the observed decrease in diurnal temperature range at five urban areas during the 30 years period.

• Journal of Environmental Health Sciences
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• v.37 no.6
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• pp.397-405
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• 2011

Objectives: The impact of climate change on the health has been of increasing concern due to a recent temperature increase and weather abnormality, and the research results of the impact varied depending on regions. We synthesized risk estimates of the overall health effects of low and high temperature taking account of the heterogeneity. Methods: A comprehensive literature search was conducted using PUBMED to identify journal articles of low and/or high temperature effects on mortality. The search was limited to the English language and epidemiological studies using time-series analysis and/or case-crossover design. Random-effect models in meta analysis were used to estimate the percent increase in mortality with $1^{\circ}C$ temperature decrease or increase with 95% confidence intervals (CI) in cold or hot days. Results: Twenty three studies were presented in two tables: 1) low temperature effects; 2) high temperature effects on mortality. The combined effects of low and high temperatures on total mortality were 2% (95% CI, 1-4%) per $1^{\circ}C$ decrease and 4% (95% CI, 2-5%) per $1^{\circ}C$ increase of temperature, respectively. Conclusions: This meta analysis found that both low and high temperatures affected mortality, and the magnitude of high temperature appeared to be stronger than that of low temperature.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1997.04a
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• pp.151-166
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• 1997

ER clutch is a device using ER fluid, so called "intelligent material" and is a controlled system with electric field strength. Current problem of this device is that the temperature of ER fluid increases when ER clutch is operating and affects the performance of ER clutch. This study was undertaken to estimate this performance variation due to temperature increase of ER fluid. Analytic power transmission relationships and the temperature increase model using the rheological model of ER fluid were developed and the dynamic model of proposed ER clutch system was constructed, also. With this relationships, effects of changing geometric, kinetic parameters of ER clutch and ER fluid properties were described and performance variations due to temperature increases of ER fluid were estimated. In conclusion, compared with neglecting temperature increase effects, a performance of ER clutch was very differential. Therefore, to achieve uniform performance of ER clutch, we have to improve thermal stability of ER fluid with a view point of material development and design carefully ER clutch considering temperature increase effects with a view point of mechanical design skill.ign skill.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.25 no.2
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• pp.82-86
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• 1989

This paper is concerned with the effects of temperature of diesel fuel on combustion characteristics and engine performance in a home-made precombustion diesel engine for small-sized fishing boat. The results may be summarized as follows: 1. The fuel injection timing was delayed with increase in temperature for diesel fuel, and remarkably delayed at low load. 2. The point of maximum pressure was delayed with increase in temperature for diesel fuel, the maximum pressure decreased with increase in temperature for diesel fuel but increased with increase in load. 3. The brake specific fuel comsumption (BSFC) decreased with increase in load, the optimum temperature of the heated fuel was about 15$0^{\circ}C$. 4. The smoke emissions increased with increase in load and temperature for diesel fuel.

• Annals of Clinical Neurophysiology
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• v.8 no.2
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• pp.125-134
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• 2006

Among the various physiological factors that affect nerve conduction velocity (NCV), temperature is the most important. Because the influence of temperature is the most important source of error. It is known from animal experiments that conduction is eventually completely blocked at low temperatures, the myelinated A fibers being the first affected and the thin fibers of group C the last. Many studies showed that the NCV decreases linearly with lowering temperature within the physiological range. The distal motor latency increased by $0.2msec/^{\circ}C$ drop in temperature between $25^{\circ}C$and $35^{\circ}C$ in the median, ulnar and peroneal nerves. The temperature affect the neuromuscular transmission; The miniature endplate potential (MEPP) and endplate potential (EPP) are increase with increasing temperature. In myasthenia gravis, the reduction in the decremental response is observed following cooling. The lowering temperature make increase the amplitude of sensory compound action potential; make enlarge the surface area of compound muscle action potential with very little increase in amplitude; make diminish the fibrillation potential and increase the myotonia in needle electromyography (EMG). Because of these findings mentioned above, the skin temperature should be routinely monitored and controlled during nerve conduction tests and needle EMG and should be taken into account when interpreting the findings.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.602-608
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• 2009

In this thesis, output voltage, current and power of solar module were classified by irradiation from data of overall operating characteristics collected for one year in order to manage efficient photovoltaic generation system and deliver maximum power. In addition, from these data, correlations between irradiation of photovoltaic cell and amount of power given by photovoltaic cell was quantitatively examined to deduce optimization of the design and construction of photovoltaic generation system. As I-V characteristics according to a temperature range of 10~50[$^{\circ}C$], the area of I-V characteristics were increased with an increase in temperature. Since this area corresponds to the power, output power is thought to have increased with temperature. As output power characteristics according to a temperature range of 10~50[$^{\circ}C$], output power was increased with an increase in temperature. Since output power increases with temperature increase, the result corresponds well to the related equation on temperature and output power. As I-V characteristics according to a irradiation range of 100~900 [$W/m^2$], voltage and current were increased with an increase in irradiation. The result is thought of as an increase in output power with increasing irradiation. As output power characteristics according to a irradiation range of 100~900 [$W/m^2$], output power was increased with increasing irradiation. This result corresponds well to the related equation on irradiation and output power.

• Structural Engineering and Mechanics
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• v.74 no.6
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• pp.747-756
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• 2020

High-strength concrete (HSC) generally is made with high amount of cement which may release large amount of hydration heat at early age. The hydration heat will increase the internal temperature of slab and may cause potential cracking. In this study, slab specimens with a dimension of 600 × 600 × 100 mm were cast with concrete incorporating silica fume for test. The thermistors were embedded in the slabs therein to investigate the interior temperature development. The test variables include water-to-binder ratio (0.25, 0.35, 0.40), the cement replacement ratio of silica fume (RSF; 5 %, 10 %, 15 %) and fly ash (RFA; 10 %, 20 %, 30 %). Test results show that reducing the W/B ratio of HSC will enhance the temperature of first heat peak by hydration. The increase of W/B decrease the appearance time of second heat peak, but increase the corresponding maximum temperature. Increase the RSF or decrease the RFA may decrease the appearance time of second heat peak and increase the maximum central temperature of slab. HSC slab with the range of W/B ratio of 0.25 to 0.40 may occur cracking within 4 hours after casting. Reducing W/B may lead to intensive cracking damage, such as more crack number, and larger crack width and length.