• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.39-42
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• 2014

The objective of this study was to estimate cardinal temperatures for germination of lettuce (Lactuca sativar L.) using bilinear, parabolic, and beta distribution functions. Seeds of lettuce were germinated in a growth chamber at 7 constant temperatures: 10, 14, 16, 20, 24, 28, and $32^{\circ}C$. Four replicates of 100 seeds were placed on two layers of filter paper in a 9 cm petri-dish. Radicle emergence of 1 mm was scored as germination. The time course of germination was modeled using a logistic function. These minimum, optimum, and maximum temperatures were estimated by regression of the inverse of time to 50% germination rate against the temperature gradient. In bilinear function, minimum, optimum, and maximum temperatures were $7.9^{\circ}C$, $23.3^{\circ}C$, and $28.0^{\circ}C$, respectively. In parabolic function, minimum, optimum, and maximum temperatures were $9.7^{\circ}C$, $19.5^{\circ}C$, and $29.4^{\circ}C$, respectively. In beta distribution function, minimum, optimum, and maximum temperatures were $3.7^{\circ}C$, $20.7^{\circ}C$ and $32.0^{\circ}C$, respectively. Minimum, optimum, and maximum ranges of temperatures were $3.7{\sim}9.7^{\circ}C$, $19.5{\sim}23.3^{\circ}C$, and $28.0{\sim}32.0^{\circ}C$, respectively.

• Journal of Korean Society of Steel Construction
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• v.28 no.6
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• pp.449-458
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• 2016

The temperature data were measured for two years in a bridge specimen and the bridge in service nearby in order to calculate the effective temperature for thermal loads in steel box girder bridge. The maximum and minimum effective temperatures were calculated in the bridge specimen and the bridge according to air temperature in 2014, 2015 and 2years. The effective temperatures calculated in this study were compared the Euro code and the Highway Bridge Design Criteria. The coefficients of determination in the maximum effective temperature and the Euro code for 2 year were calculated from R = 0.927, R = 0.894 in a bridge specimen and the bridge respectively. Those of minimum temperature and the Euro code were analyzed from R = 0.992, R = 0.813 in two bridge respectively. Also, the results were evaluated as being very similar, or slightly increased as compared with the maximum temperature of the Korean Highway Bridge Design Code(Limit State Design).

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.88-89
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• 2001

꿀벌의 실내월동에 이용되는 월동용 저온양봉사의 내부환경에 영향을 주는 요소에는 외기온, 저장봉군수, 환기량 등이 있다. 이러한 환경요인을 고려하여 설계 제작된 국내 월동용 저온양봉사의 성능 및 저장봉군수와 양봉사 내부온도의 관계를 분석하고자 경상북도의 7개 지역에 설치된 월동용 저온양봉사(내부크기 폭4.5m×길이3m×높이3m)에 대하여 2000. 11. 25부터 2001, 2. 15까지 실내월동 실험을 수행하였다. 실험대상 지역은 포항, 문경, 상주, 칠곡, 성주, 영양, 안동이며, 지역별 저장봉군수는 각각 14, 74, 85, 110, 163, 170, 260군이다(Table 1). 꿀벌의 월동기간 중 안동과 성주지역을 제외한 5개 지역의 실내 월동성적은 폐사율이 10％미만으로 대체적으로 우수한 것으로 조사되었으나, 월동기간중 지역별 외기온을 분석한 결과, 평균외기온 및 최저외기온이 가장 낮은 지역은 안동이었으며, 그 값이 각각 -3.1℃와 -9.4℃일 때 양봉사 내부의 평균온도와 최저온도는 5.2℃와 3.8℃로 나타났다. 반면에 평균외기온 및 최저외기온이 가장 높은 지역은 포항이었으며 그 값이 각각 1.3℃와 -4.1℃일 때 양봉사 내부의 평균온도와 최저온도는 각각 3.1℃와 1.2℃로 나타나 저온양봉사 내부의 온도환경 조절성능이 모두 우수한 것으로 판단되었다(Table 1). 또한 월동기간중 주.야간으로 양봉사 내.외부의 온도변화를 분석한 결과, 저장봉군수의 증가에 따라 주야간 모두 양봉사 내.외부 온도편차가 증가하는 경향을 나타내었으며 양봉사 내부의 주.야간 평균온도는 모두 꿀벌의 월동에 적정한 범위인 2℃-9℃를 유지하는 것으로 분석되었다(Table 2). 그리고, 월동기간중 외기온이 가장 낮은 시기(1월 13-19일)의 평균 외기온이 -8℃--9℃로 유사한 문경, 상주, 영양, 안동지역의 월동용 저온양봉사의 평균 내부온도는 각각 -2.0℃, -1.0℃, 0.2℃, 4.2℃로 나타나 저장봉군수가 증가함에 따라 월동용 저온양봉사의 내부온도가 증가하여 꿀벌의 월동에 적합한 온도범위를 유지함을 알 수 있었다. 실험기간동안 대부분의 저온양봉사 내부온도는 꿀벌이 월동하기에 적정한 온도범위(2℃-9℃)로 유지하였다(Fig. 1).

• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.403-407
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• 2008

Relations between variation of SSTs(sea surface temperatures) in the South Sea of Korea and intensity of typhoons which passed through the South Sea of Korea was analyzed for 36 years from 1970 to 2005. The SSTs in the South Sea show the rising trends continuously. The mean SST of the last 10 years(1996-2005) is higher $1.03^{\circ}C$ than the mean SST during 10 years(1970-1979). The rising trends are especially strong after 1994. The intensity of typhoon can be shown by the minimum sea level pressure. The minimum sea level pressures of typhoons which passed through the South Sea show the descending trends. The mean minimum sea level pressure of the last 10 years(1996-2005) is lower 10.1hPa than that during 10 years(1970-1979). The correlation analysis shows that the rising of SSTs in the South Sea has relations with the strengthening of intensity of typhoons.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.226-230
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• 2009

To investigate the effect of night minimum temperature on growth and flower development in standard type chrysanthemum 'Baekina' during winter season, morphological characteristics and physiological disorders were compared with standard chrysanthemum 'Jinba'. Although the flower budding of 'Baekma' was delayed about 2 to the days compared with 'Jinba', the days to flowering of 54 to 59 showed no difference between the two cultivars. Flowering was delayed as minimum temperature decreased at night. The length and weight of cut flower decreased in the two cultivars as minimum temperature increased at night. In 'Baekina', the number of petals at 16 showed the highest values among other temperatures. Whereas there was no significant difference among the temperature treatments in 'Jinba'. Rosette occured only in 'Baekma', and the ratio was 11.1% at 14, 55.6% at 16, and 56.1% at 18. The inhibition of flower budding appeared only at 14 in the ratio of 17.3% in 'Baekma' and 4.0% in 'Jinba'.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.8
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• pp.1078-1084
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• 2011

In this paper, a temperature control for LED(Light Emitting Diode) lamp using a cooling fan is studied. An efficient temperature control scheme for the LED lamp using the fan wind at the lowest sound noise is studied. Also, for minimization study of sound noise and temperature control of an LED lamp, a sequential control algorithm using the cooling fan at the lowest sound noise is presented. For the study, after measurement of the minimum sound noise of the fan and related temperature of the LED lamp through tests, experiments on temperature control of the LED lamp using the fan was performed.

• Journal of agriculture & life science
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• v.53 no.2
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• pp.121-129
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• 2019

This study carried out to determine control factors for the improvement of productivity of laying hens suffering heat stress during hot weather. A total of 48,451 ISA Brown layers were housed in a farm located in Gyeongsangnam-do, Republic of Korea. Five thermo-hydrometer loggers were installed inside the house to collect data of dry-bulb temperature and relative humidity. The experiment continued for 81 days when the summer season begins from 19th June to 7th September, 2018. This study analyzed the correlations among layers' production index and daily average, highest, and lowest temperature; daily average, highest, and lowest relative humidity; and daily average, minimum, and maximum THI. The result indicated that feed consumption, hen-day egg production, egg weight, and FCR decreased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.01). On the other hand, water intake increased as the daily average, highest and lowest dry-bulb temperature and THI rise (p<0.001). The relative humidity was not considered to have direct correlations to the layers' production index (p>0.05). However, it was noticeable that the mortality did not have significant relations with daily average and highest temperature; THI; or daily average, highest and lowest relative humidity while it was relevant to the daily lowest temperature and THI (p<0.05). In conclusion, to enhance the productivity of laying hens in a hot climate, it is recommended that daily average, highest, and lowest dry-bulb temperature and THI are maintained as low as possible. Especially, the daily lowest temperature is needed to lower to 20℃, which is the lowest critical temperature for layers.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.163-167
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• 2002

This study was carried out to investigate the effect of minimum night temperature in the PE house on growth of seedlings of Pinus densiflora and Betula platyphylla in winter season. The experiment was performed with three minimum night temperature regimes,5~8$^{\circ}C$, 10~13$^{\circ}C$ and 15~18$^{\circ}C$. The temperature regimes were maintained for 8 weeks (to April 6) after germination peak, and then were broken by increasing natural temperature. The temperature did not affect the germination rate but delayed the germination by 10 days. Height, root collar diameter growth, and dry weight of two species were reduced by relatively low night temperature. The reduction was more obvious in the dry weight of above the ground measured at 8 weeks after germination. The seedlings grown for 8 weeks at 5~8$^{\circ}C$ showed the lowest T/R ratio. It was also observed that the height growth response in Betula platyphylla seedlings to relatively low temperature was more sensitive than Pinus densiflora.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.151-158
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• 1997

This study was carried out to identify how soybean seed oil is influenced by climatic factors and to investigate how genotypes differ in their responses. Twelve lines selected were studied in 13 environments of North Carolina. Responses of oil concentration and total seed oil to climatic variables were investigated using a linear regression model. The best response models were determined. There were wide climatic effects in oil concentration and total seed oil. The lowest oil concentration environment was characterized by the most HTD and the smallest VADTRg and the lowest total oil environment was distinguished by the largest VADTRa and the smallest VMnDT. For oil concentration, most lines except for NC107 responded negatively to MxDT, HTD, ADT, and ADTRg, although they had different degrees of sensitivities, indication that warmer temperature may result in decreased oil concentration. All lines responded positively to VMnDT, VADTRg, and ADRa, although they had different degrees of sensitivities, suggesting that larger variation in minimum daily temperature and average daily temperature range and more average daily rain may result in increased oil concentration. Eleven lines had best response models with 1 to 3 variables. However, although NC109 did not show a significant sensitivity to any variable, it had the best response model with 2 significant variables, demonstrating that an interaction between 2 variables might be more critical in determining oil concentration than one variable.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.198-199
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• 2007

Relation between SSTs(Sea Surface Temperatures) in the South Sea and intensity of typhoons which passed through the South Sea was analyzed for 36 years from 1970 to 2005. The SSTs in the South Sea show the rising trends continuously. The mean SST of the last 6 years(2000-2005) is higher 1.21$^{circ}C$ than the mean SST during 10 years(1970-1979). The rising trends are especially strong after 1994. The intensity of typhoon am be seen by the central pressure. The minimum central pressures of typhoons which passed through the South Sea show the descending trends. The mean minimum central pressure of the last 6 years(2000-2005) is lower 9hPa than t1m during 10 years(1970-1979). The correlation analysis shows that the rising of SSTs in the South Sea has relations with the strengthening of intensity of typhoons.