• 천문학회보
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• 제43권2호
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• pp.58.1-58.1
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• 2018

In the solar atmosphere, below the region of temperature minimum, temperature decreases with height and above it, temperature increases with height. Therefore the inference of temperature minimum is a basis of the study about the solar atmosphere and heating problem. The temperature of the temperature minimum region can be inferred from acoustic cutoff frequency. According to a recent study the acoustic cutoff frequency is related to the peak frequency of the power spectrum the chromospheric three-minute velocity oscillations. Using this relationship, we infer the temperature of temperature minimum. The three minute velocity oscillation and its power spectrum are obtained for a pore observed with the Fast Imaging Solar Spectrograph (FISS) $H{\alpha}$ band. We present the inferred temperature and compare it with the temperature of Maltby model. We also investigate the effect of the inclination of magnetic field on the temperature minimum.

• 한국환경과학회지
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• 제21권4호
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• pp.401-409
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• 2012

This study examines the climatological variability of urban area and the increase of temperature by urbanization using the observed data of Busan and Mokpo during the last 100 years (1910~2010). The results are as follows. First, the maximum temperature in Busan during the last 100 years has increased by $1.5^{\circ}C$ while average temperature and the minimum temperature have increased by $1.6^{\circ}C$ and $2^{\circ}C$. In Mokpo, the maximum temperature and average temperature have increased by $1^{\circ}C$ and the minimum temperature has increased by $0.8^{\circ}C$. The increase of urban temperature appeared to be higher in Busan than in Mokpo by $0.5^{\circ}C{\sim}1.2^{\circ}C$. Second, as for the change in temperature before and after urbanization, the maximum temperature, average temperature and the minimum temperature during last 50 years compared to the previous 50 years have increased about $1.5^{\circ}C$, $1.6^{\circ}C$ and $2.1^{\circ}C$, however, the predicted temperature after removing urbanization effect was estimated to be increased by $1^{\circ}C$. The proportion that urbanization takes on the overall increase of temperature appeared to be 33% at the maximum temperature, 37.5% at average temperature and 52.3% at the minimum temperature, thus the proportion of urbanization appeared to be maximized at the minimum temperature.

• 한국안전학회지
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• 제16권3호
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• pp.83-88
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• 2001

This study was preformed by measuring the minimum ignition temperature of MBS according to the change of sample vessel size and the minimum ignition temperature of MBS dust cloud The minimum ignition temperature of MBS product decreased as the vessel size was large, and it was obtained in the range from $120.5^{\circ}C$ to $94.5^{\circ}C$ and the apparent activation energy was obtained with 32.94Kcal/mol. The minimum ignition temperature of MBS dust cloud was measured by using Godbert-Greenwald furnace and it was obtained at $407^{\circ}C$ with the sample of 0.4g in the air and the ignition of dust cloud was not occurred below 13% oxygen concentration.

• 대한지리학회지
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• 제43권6호
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• pp.824-842
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• 2008

본 연구는 서리에 의한 피해를 최소화하기 위하여 서리 발생일의 기상 요소별 특성을 분석하여 서리가 발생할 수 있는 기상 조건을 파악하였다. 첫서리 현상이 발생하는 시기인 가을과 마지막 서리 현상이 나타나는 봄으로 나누어 서리 현상일의 기압계 유형, 최저기온, 초상최저기온, 일교차, 평균 상대습도, 최소상대습도, 평균 풍속 자료를 분석에 이용하였다. 기압계 유형별로는 우리나라 남서쪽에 중심을 둔 이동성 고기압의 영향을 받고 있을 때 서리 현상은 가장 잘 발생했다. 초상최저기온은 지표에 발생하는 서리 현상을 감지하기 때문에 농업적 목적으로는 최저기온보다 더 중요하다. 본 연구에서도 해안지역의 경우는 최저기온이 영상이어도 서리가 발생했으나 서리 발생일의 초상최저기온은 모든 지역에서 영하였다. 서리 현상일의 일교차는 내륙 지역은 $14^{\circ}C$ 이상이었으며, 해안 지역은 $9{\sim}12^{\circ}C$이었다. 서리 현상이 발생하기 위한 최소상대습도는 $30{\sim}50%$였으며, 내륙 지역이 해안 지역보다 낮았다. 풍속은 약할수록 서리가 발생하기 쉬우므로 대부분 지역에서 서리가 발생한 날의 평균 풍속은 2m/sec 이하였으며 일부 도서 지역과 해안 지역에서는 $4{\sim}6m/sec$를 나타냈다.

• 대한지리학회지
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• 제49권1호
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• pp.32-44
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• 2014

본 연구에서는 중부지방의 1월 최저기온 분포 특성을 파악하고 철원의 극한 최저기온의 원인을 규명하고자 하였다. 이를 위해 중부지방 25개 관측소의 1991~2010년 1월 기온 분포 특성과 철원 기온과 춘천, 홍천, 봉화, 대관령, 원주, 제천 등 중부내륙 지역의 기온 차이를 기압배치형에 따라 분석하였다. 일평균기온과 평균 일최저기온은 철원과 해발고도가 높은 지역에서 낮게 나타나지만, $-15^{\circ}C$ 이하 일수와 같은 극한기온의 출현빈도는 철원에서 두드러졌다. 시베리아 고기압이 확장하거나 우리나라 북쪽에 이동성 고기압이 위치할 때 철원 기온이 비교지점에 비해 상대적으로 더 낮다. 이동성 고기압의 영향을 받을 때는 철원과 비교지점 간 기온 차이가 적거나, 봉화, 제천과 같은 분지의 기온이 더 낮다.

• 대기
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• 제17권2호
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• pp.185-193
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• 2007

This study investigates urbanization effect in warming trend of surface air temperature over Korea. The data used in this study consist of the daily minimum and maximum temperatures during the period of 32 years(1968-1999) from 16 stations of KMA. To calculate magnitude and trend of urbanization effect, stations were classified into urban and rural stations using population statistics. Urban stations were defined as those with population densities greater than 1000 persons per kilometer squared in 1995. The others were defined as rural stations. The urban stations were also subdivided into two groups according to their population totals. For estimates of urban effect magnitude, temperature change was calculated by comparing 16-year mean values between 1968-83 and 1984-99. Then, the difference between each urban station and every rural station was calculated. During the analysis period of 32 years, maximum temperature increase is $1.22^{\circ}C$. In the total temperature increase, urban effect is estimated by 28.7%. For minimum temperature, it becomes larger by about 10% than that in maximum temperature. Therefore, urban effect in an increasing trend of minimum temperature is 38.9% in the change of $1.13^{\circ}C$.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.63-68
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• 2008

Efforts tp overcome the current challenge of global warming and abnormal temperature are being taken around the world. According to a report, average temperature of Korea has increased by about $0.8^{\circ}C$ for a century. In particular, temperature has rapidly increased since year 2000. Climate changes have brought remarkable changes in our lives. For example, agricultural field will see changes in crops and production. Energy used to maintain and manage architectures will be changed as well. In order to actively cope with rapidly changing global climate which drives changes from the basic behavior of our lives to subtle changes, international cooperation and researches are performed around the word. For instance, as a part of these global efforts, research on typical meterological data for computer simulation program to evaluate architecture energy performance is in progress in Korea. In order to conduct research on typical meterological data in format of data per time, reference regarding monthly maximum/minimum temperature time is required. Unfortunately, however, reference regarding maximum/minimum temperature time hasn't been defined in Korea. Therefore, this study aims to provide fundamental data essential for various researches by calculating maximum/minimum temperature time of major cities across Korea. According to the study, maximum temperature occurs at 3 p.m and minimum temperature occurs at 5 a.m or 6 a.m. respectively, in overall areas.

• 한국초전도ㆍ저온공학회논문지
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• 제21권3호
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• pp.1-5
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• 2019

The superconductor stability theories are consistently described by the integral formula. If the defined stability function is a simple decreasing function, it becomes a cryogenic stability condition. If the stability function has a maximum value and a minimum value, and the maximum value is less than 0, then it is a cold-end recovery condition. If the maximum value is more than 0, it can be shown that the unstable equilibrium temperature, that is, the MPZ (minimum propagation zone) temperature distribution can exist. The MPZ region is divided into two regions according to the current ratio. At the low current ratio, the maximum dimensionless temperature is greater than 1, and at the relatively high current ratio, the maximum dimensionless temperature is less than 1. In order to predict the minimum quench energy, the dimensionless energy was obtained for the MPZ temperature distribution. In particular, it was shown that the dimensionless energy can be obtained even when the MPZ maximum temperature is 1 or more.

• 한국환경과학회지
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• 제23권9호
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• pp.1619-1626
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• 2014

We analyzed diurnal variations in the surface air temperature using the high density urban climate observation network in Daegu metropolitan city, the representative basin-type city in Korea, in summer, 2013. We used a total of 28 air temperature observation points data(16 thermometers and 12 AWSs). From the distribution of monthly average air temperature, air temperature at the center of Daegu was higher than the suburbs. Also, the days of daily minimum air temperature more than or equal to $25^{\circ}C$ and daily maximum air temperature more than or equal to $35^{\circ}C$ at the schools near the center of Daegu was more than those at other schools. This tendency appeared more clearly on the days of daily minimum air temperature more than or equal to $25^{\circ}C$. Also, the air temperature near the center of the city was higher than that of the suburbs in the early morning. Thus it was indicated that the air temperature was hard to decrease as the bottom of the basin. From these results, the influence of urbanization to the formation of the daily minimum temperature in Daegu was indicated.

• International Journal of Industrial Entomology and Biomaterials
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• 제17권2호
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• pp.173-180
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• 2008

The influence of temperature and relative humidity in infection and cross-infection of Nosema bombycis and N. mylitta respectively in mulberry silkworm, Bombyx mori L. on larval mortality, multiplication of pathogens, larval weight and growth rate in three different seasons were studied. Seasons were selected in such condition, when very less fluctuations between minimum and maximum temperature and minimum and maximum relative humidity ($25{\sim}28^{\circ}C$ and $65{\sim}72%$ R.H) was observed i.e., season-1. Fluctuations between minimum and maximum temperature were less ($28.05{\sim}34.50^{\circ}C$) but R.H % was more ($55{\sim}81%$) in season-2. Fluctuations between minimum and maximum temperature and R.H % were more ($20.00{\sim}40.5^{\circ}C$ and $64.00{\sim}90.00%$) in season-3. Growth rate of microsporidian-infected silkworm is directly related to the prevailing temperature and relative humidity in silkworm. Silkworm can tolerate slight variation of temperature but slight variation of relative humidity disfavours the development of silkworm and favours the multiplication of pathogens.