• 한국환경과학회지
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• 제10권2호
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• pp.143-151
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• 2001

The atmospheric conditions and the transport mechanism of long-range transport of air pollutants from coastal area to inland area were investigated using regular meteorological data and air pollution data obtatined from the southeastern area of Korea. Daytime temperature over the inland area(Taegu) was higher than that over the coastal area(Pusan) and the temperature difference of about 5~6$^{\circ}C$ when the thermal low most fully developed and the sea level pressure over Taegu was lower than that over Pusan by about 4~5hPa at that time. Therefore this low pressure appeared to the thermally induced low. Air mass polluted from the coastal area during the morning period was transported inland area, at first by the sea breeze and by the large scale wind system toward the thermal low generated in the mountainous inland region. This was explained by the fact that the concentration of air pollutants over Taegu increased throughtout the late afternoon.

• 대한기계학회논문집B
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• 제38권3호
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• pp.243-254
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• 2014

고속 저토크 표면 부착 영구자석형 동기 전동기의 운전 안정성 확보를 위하여 과속도 및 과부하 영역에서 전동기 코일 온도 예측이 필수적이다. 0.35mm 의 S18, S08 등급인 35PN440, 35PN220 그리고 0.15mm 의 저손실 재료인 15HTH1000 으로 제작된 고정자 철심을 포함하는 전동기의 정격 구동 조건에서 손실 및 코일 온도를 측정하여 과속도 및 과부하 영역의 손실 및 열저항을 예측하고 열전달 모델링을 수행하였다. 이의 검증을 위하여 무부하 과속도 영역에서 계산된 코일 온도와 실험값을 비교하여 6.4%이하로 일치하였다. 35PN440 을 적용한 전동기에 비하여 15HTH100 을 적용한 전동기는 무차원 회전속도 0.9, 부하율 3.0 일 때 철손실이 84.4% 로 감소하였고, 무차원 코일 온도 1.0 을 기준으로 출력이 85.2% 향상되었다. 정격 구동 영역의 손실 측정 및 열전달 모델링으로 과부하 및 과속도 영역에서 철심재질에 따른 코일 온도 변화 및 전동기 출력 개선량을 정확하게 예측할 수 있음을 알 수 있다.

• 대기
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• 제18권3호
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• pp.199-206
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• 2008

This study employs a structural time series method in order to model and estimate stochastic trend of surface temperatures of the globe, Northern Hemisphere, and Northeast Asia ($20^{\circ}N{\sim}60^{\circ}N$, $100^{\circ}E{\sim}150^{\circ}E$). For this study the reanalysis data CRUTEM3 (CRU/Hadley Centre gridded land-surface air temperature Version 3) is used. The results show that in these three regions range from $0.268^{\circ}C$ to $0.336^{\circ}C$ in 1997, whereas these vary from $0.423^{\circ}C$ to $0.583^{\circ}C$ in 2007. The annual mean temperature over Northeast Asia has increased by $0.031^{\circ}C$ in 2007 compared to 1997. The climate change in surface temperatures over Northeast Asia is slightly higher than that over the Northern Hemisphere.

• 설비공학논문집
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• 제15권4호
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• pp.287-293
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• 2003

This study examined the temperature-dependent regression model of energy consumption based on various measuring period. The methodology employed was to construct temperature-dependent linear regression model of daily energy consumption from one day to three months data-sets and to compare the annual heating energy consumption predicted by these models with actual annual heating energy consumption. Heating energy consumption from a building in Daejon was examined experimentally. From the results, predicted value based on one day experimental data can have error over 100%. But predicted value based on one week experimental data showed error over 30%. And predicted value based on over three months experimental data provides accurate prediction within 6% but it will be required very expensive.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.257-260
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• 2003

Bi-2223 tape is one of the most widely used HTS tapes for power application. This paper presents the basic properties such as temperature and resistivity rise of the Bi-2223 tape which is exposed to the over current. Temperature and resistivity were measured by E-type thermocouple and voltage taps. Results of the measurement showed that rise of voltage depended on the magnitude of the over current until several times of the rated current. When the current largely exceeded the rated current, rise of voltage depended on the magnitude of the resistivity of the Ag matrix because temperature of the matrix increased to a great extend.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1154-1156
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• 2003

본 논문은 IPM의 구동부, 과열, 과전류, 단락 및 제어부의 부족전압 제어하는 IC의 설계중 Over-Temperature protection기능에 대한 것으로서 기존의 온도센서나 과열검출 Tr을 사용하지 않고, 온도에 따른 MOSFET의 Rds(on)변화를 검출하여 과열을 방지하는 Direct Over Temperature protection기능을 PSpice를 이용하여 modelling하고 simulation 한 결과에 대해서 기술하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.284-285
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• 2005

Bi-2223 High-Temperature Superconducting(HTS) tape is one of the most widely used HTS tape for power application. Characteristics of the over current of HTS tape with different sheath are described. This paper presents the basic properties such as temperature and resistivity rise of the Bi-2223 HTS tape which is exposed to the over current. It is expected that results from this study can be utilized as basic data in designing superconducting power devices.

• 한국수산과학회지
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• 제30권6호
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• pp.974-983
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• 1997

The Okhotsk Sea is unique natural object with climatic peculiarities. The climate of the Okhotsk Sea results from the general distribution of solar radiation during a year, and the characteristics of the atmospheric circulation that varies through a year: In cold half year the main pressure formations are Siberian high and Aleutian low. Asian low centered on Afghanistan dominates over the Asian continent in summer. The North-Pacific sea surface is under effect of permanent North Pacific high. The changes in their position from year to year are very significant. The anticyclonic activity over the Far Eastern Seas is one of the main factors for the formation of weather anomalies over the adjacent territories. The analysis of summer weather characteristics over the coast of Okhotsk and East Sea using the data obtained from Hydrometeorological stations during $1949\~1990$ showed that, to a great extent, distribution of the air temperature depends on thermal state of the Okhotsk Sea and atmospheric circulation over it. We show some relations between weather characteristics and the intensity of atmospheric action center for the North Pacific high in summer when its ridge propagates to Okhotsk Sea. Correlation coefficients between air pressure over the Okhotsk Sea and air temperature for the coastal areas reach up to 0.7. Analysis of the spatial-temporal distribution of main meteorological values over the Okhotsk Sea such as air pressure, and air temperature are also performed.

• 대기
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• 제32권4호
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• pp.297-306
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• 2022

We examined potential seasonal prediction of the Korean surface temperature using the relationships between the Arctic Sea Ice Area (SIA) in autumn and the temperature in the following July and February at 850 hPa in East Asia (EA). The Surface Air Temperature (SAT) over Korea shows a similar relationship to that for EA. Since 2007, reduction of autumn SIA has been followed by warming in Korea in July. The regional distribution shows strong correlations in the southern and eastern coastal areas of Korea. The correlations in the sea surface temperature shows the maximum values in July around the Korean Peninsula, consistent with the coastal regions in which the maximum correlations in the Korean SAT are seen. In February, the response of the SAT to the SIA is the opposite of that for the July temperature. The autumn sea ice reduction is followed by cooling over Korea in February, although the magnitude is small. Cooling in the Korean Peninsula in February may be related to planetary wave-like features. Examining the autumn Arctic sea ice variation would be helpful for seasonal prediction of the Korean surface temperature, mostly in July and somewhat in February. Particularly in July, the regression line would be useful as supplementary information for seasonal temperature prediction.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권7호
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• pp.317-322
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• 2002

This paper presents a linear temperature/voltage relation over a temperature range(0~100$^{\circ}C$) with high-resolution, reasonably god response linearity, reliability, and overall improved performance. A notable feature of the proposed method is that the whole temperature span is divided by 16 subbands thus the variation span of measured voltage is narrowed. Therefore noise characteristic has been improved. The output voltage is amplified after the uniformed DC voltage component is eliminated by offset. We proposed circuit using median value and mean value of digital signal in order to reduce the noise effect. The proposed circuit offers linear temperature/voltage conversion over a wide dynamic range using DSP(TMS320C31) and steinhart equation.