• 한국자기학회지
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• 제5권5호
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• pp.762-766
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• 1995

The coercive field $H_{c}$ of amorphous Y-Fe alloys in the spin-glass state has been investigated. Foramorphous $Y_{10}Fe_{90}$ alloy, the thermal variations of $H_{c}$ in the maximum external field $H_{max}=300,\;600$ and 1 k Oe exhibit a maximum. Since spin-glass behavior is strongly affected by external magnetic fields, the maximum point moves to lower temperature with increasing $H_{max}$. The appearance of the maximum in $H_{c}$ has been discussed in terms of the change of the spin-glass state in the external magnetic field. When the value of $H_{max}$ is 55 kOe, the temperature dependence of $H_{c}$ has no maximum and shows an exponential decrease with increasing temperature. Similar trends have been observed over a wide concentration range. The concentration dependence of $H_{c}$ is associated with the magnetic phase diagram.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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• pp.291-296
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• 2003

This study estimated surface temperature by using split-window technique and NOAA/AVHRR data was used. For surface monitoring, cloud masking procedure was carried out using threshold algorithm. The daily maximum air temperature is estimated by multiple regression method using independent variables such as satellite-derived surface temperature, EDD, and latitude. When the EDD data added, the highest correlation shown. This indicates that EDD data is the necessary element for estimation of the daily maximum air temperature. We derived correlation and experience equation by three approaching method to estimate daily maximum air temperature. 1) non-considering landcover method as season, 2) considering landcover method as season, and 3) just method as landcover. The last approaching method shows the highest correlation. So cross-validation procedure was used in third method for validation of the estimated value. For all landcover type 5, the results using the cross-validation procedure show reasonable agreement with measured values(slope=0.97, intercept=-0.30, R$^2$=0.84, RMSE=4.24$^{\circ}C$). Also, for all landcover type 7, the results using the cross-validation procedure show reasonable agreement with measured values(slope=0.993, Intercept=0.062, R$^2$=0.84, RMSE=4.43$^{\circ}C$).

• 한국세라믹학회지
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• 제34권7호
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• pp.767-773
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• 1997

Thermal shock behavior of alumina ceramics were studied by quenching the heated alumina specimen into the water of various temperatures over 0~10$0^{\circ}C$. The critical thermal shock temperature difference ( Tc) of the specimen decreased almost linearly from 275$^{\circ}C$ to 20$0^{\circ}C$ with increase in the cooling water temperature over 0~6$0^{\circ}C$. It is probably due to the increase of the maximum cooling rate which is dependent of the convection heat transfer coefficient. The convection heat transfer coefficient is a function of the temperature of the cooling water. However, the critical thermal shock temperature difference( Tc) of the specimen increased at 25$0^{\circ}C$ over 80~10$0^{\circ}C$ due to the film boiling of the cooling water. The maximum cooling rate, which brings about the maximum thermal stress of the specimen in the cooling process, was observed to increase linearly with the increase in the quenching temperature difference of the specimen due to the linear relationship of the convection heat transfer coefficient with the water temperature over 0~6$0^{\circ}C$. The critical maximum cooling rate for thermal shock fracture was observed almost constant to be about 260$\pm$1$0^{\circ}C$/s for all water temperatures over 0~6$0^{\circ}C$. Therefore, thermal shock behavior of alumina ceramics is greatly influenced by the convection heat transfer coefficient of the cooling water.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.927-929
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• 2003

Using received northeast region in China of Terra/MODIS data at Tokyo University of information Sciences. Make monthly division Land Surface Temperature maximum composite image. Using monthly division Land Surface Temperature maximum composite image, considered characteristic of monthly variation of Land surface temperature and relation with land covering and NDVI at the northeast region in China.

• 한국환경과학회지
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• 제28권7호
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• pp.617-627
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• 2019

This study investigated the relationship between heat-related illnesses obtained from healthcare big data and daily maximum temperature observed in seven metropolitan cities in summer during 2013~2015. We found a statistically significant positive correlation (r = 0.4~0.6) between daily maximum temperature and number of the heat-related patients from Pearson's correlation analyses. A time lag effect was not observed. Relative Risk (RR) analysis using the Generalized Additive Model (GAM) showed that the RR of heat-related illness increased with increasing threshold temperature (maximum RR = 1.21). A comparison of the RRs of the seven cities, showed that the values were significantly different by geographical location of the city and had different variations for different threshold temperatures. The RRs for elderly people were clearly higher than those for the all-age group. Especially, a maximum value of 1.83 was calculated at the threshold temperature of $35^{\circ}C$ in Seoul. In addition, relatively higher RRs were found for inland cities (Seoul, Gwangju, Daegu, and Daejeon), which had a high frequency of heat waves. These results demonstrate the significant risk of heat-related illness associated with increasing daily maximum temperature and the difference in adaptation ability to heat wave for each city, which could help improve the heat wave advisory and warning system.

• 한국환경과학회지
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• 제8권3호
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• pp.287-292
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• 1999

This study was performed to investigate the characteristics of nocturnal maxiumu ozone occurrence and the meteorological relevance using to hourly ozone data and meteorological data for 1995~1996 in Pusan coastal area. Kwangbokdong showed the highest occurrence of nocturnal maximum ozone as 36.9%, and Deokcheondong showed the lowest occurrence(9.2%) for research period in Pusan. The occurrence rates of nocturnal maximum ozone concentration were decreased toward land area. The low maximum temperature, high minimum temperature, low diurnal range, high relative humidity, high wind speed, high could amount, low sunshine and low radiation were closely related to the main meteorological characteristics occuring the nocturnal maximum concnetration of ozone. It was shown that normal daily variation of ozone concentration by strong photochemical reaction at the before day of nocturnal maximum ozone. The concnetration of nocturnal maximum ozone were occured by entrainment of ozone from the upper layer of developed mixing layer. There are no ozone sources near the ground at night, so that the nighttime ozone should be entrained from the upper layer by forced convection.

• 대한지리학회지
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• 제39권1호
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• pp.13-26
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• 2004

본 연구는 상대적 날씨 스트레스 지수로 NET의 적용 가능성을 파악하고자 하였다. 기상청에서 예보하고 있는 기온, 습도, 바람 자료를 이용하여 NET 값의 시공간적 분포 특성을 분석하였다. 여름철 스트레스 지수인 일 최고 NET의 지역별 스트레스 기준값은 바람과 습도보다는 기온의 영향을 받으므로 일 최고 기온의 분포와 유사하다. 겨울철 스트레스 지수인 일 최저 NET의 스트레스 기준값은 산지 지역과 서울 이북 지역에서는 낮은 기온의 영향을. 해안 지역에서는 강한 바람의 영향으로 기준값이 여름철에 비하여 다양하게 나타난다. 스트레스가 강한 날의 발생 빈도는 여름철은 뚜렷한 연변화가 나타나지 않지만, 겨울철에는 1990년대 중반 이후 뚜렷한 증가 경향을 보인다.

• 한국세라믹학회지
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• 제22권1호
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• pp.40-46
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• 1985

The effect of calcining temperature ranged from $700^{\circ}C$ to 110$0^{\circ}C$ on sintering characteristics of morphotropic $Pb(Zr_{0.53}Ti_{0.47})O_3 doped with $Nb_2O_5$ has been investigated. The ratio of sintered grain size to calcined grain size decreased as the calcining temperature increased. The hardness as well as the sintered density of the samples reached a maximum at about 90$0^{\circ}C$. The X-ray diffraction pattern of the sintered sample showed both tetragonal and rhombohedral phases. The tetragonal phases intensity increased with the calcining temperature going through a maximum at about 90$0^{\circ}C$ while the rhombohedral phase intensity remained uneffected. The both intensity were about the same at 90$0^{\circ}C$ The dielectric constant of the sintered samples reached a maximum um while the dielectric dissipation factor showed a minimum at the calcining temperature of about 100$0^{\circ}C$.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2003년도 기술심포지움 논문집
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• pp.270-277
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• 2003

Thermal performance of flip chip bonding with Sn-3.5Ag solder ball was studied. The temperature distribution was measured with IR(InfraRed) camera of 25 urn resolution. The measurement shows that most of the samples had much higher maximum temperature than average temperature. With central heater and 2.5 (W), the difference between maximum and average temperature is over $80^{\circ}C$. The distribution was influenced by the location of heater, the distance from heater to flip chip bonding, and the passivation opening of solder bumps. To reduce the maximum temperature, the bigger passivation opening, the smaller chip size, and the closer location of heater to flip chip bumps are preferrable.

• 미생물학회지
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• 제20권2호
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• pp.67-72
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• 1982

The effect of fermentation temperature on the production of high content alcohol has been investigated with high substrate concentration. The maximum specific growth rate, ${\mu}max\;was\;0.461hr^{-1}\;at\;35^{\circ}C$ which was the highest, whereas the maximum biomass concentration waas 8.7g/l at $25^{\circ}C$, at the growth rate lower than at $35^{\circ}C$. Approximately 140g/l of ethanol was produced in the temperature range of 20 to $25^{\circ}C$ with nearly complete comsumption of the substrate. Extended fermentation time has been required at lower temperatures, however, for the maximum values of biomass concentration and alcohol content, hence higher ethanol productivity, as the temperature was elevated to $40^{\circ}C$. The viability of yeasts was greatly improved by lowering the fermentation temperature down to $25^{\circ}C$ and also extended survival of the cells has been observed at lower fermentation temperatures, although the ethanol concentration of both waas higher.