• 대한지리학회지
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• 제52권1호
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• pp.1-13
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• 2017

이 연구에서는 서울의 1941~1970년과 1971~2000년의 평균 일최저기온의 차이와 이의 조화파 합성에서 11월 중순의 기온 상승기(온난기)와 11월 하순의 기온 정체기(한랭기)를 설정하고, 온난기와 한랭기의 평균기온의 경년변화와 이에 영향을 미치는 종관장의 특성을 조사하였다. 온난기에는 시베리아 고기압, 주변 해면기압과 925hPa 면의 바람장 등에 기온 상승에 상응하는 경년변화가 나타나지 않는다. 온난기 기온이 높은 시기(1972~1979)에는 우리나라 북부를 중심으로 고기압 편차와 고기압성 회전 편차가 나타나 겨울철 계절풍이 약화되어 기온이 상승하는 온난기가 나타나는 것으로 판단된다. 한랭기에는 시베리아 고기압은 약화되고 있으나 홋카이도 동쪽 저기압이 강화되고 우리나라 부근의 서풍이 강화되어 우리나라의 기온 상승이 억제되거나 하강하는 것으로 나타났다.

• 한국철도학회논문집
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• 제9권2호
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• pp.131-136
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• 2006

Most modern railways, especially the high speed railway tracks, use continuous welded rail(CWR) for the less maintenance. For the CWR track has very few expansion joints, track buckling has always been an unpredictable event and it happens mainly by high compressive stress in rail in summer period. Therefore, it is important to understand the variation of rail stress induced by thermal loads which has direct influence on the rail buckling and stability of railway track. This paper describes the experimental investigation of the variation of rail temperature and stress in a high speed railway track on bridge structure. Field measurement was performed to examine the correlation between the rail temperature and rail stress on the Korean High Speed Railway line. Regression functions were derived from measured data to determine the rail stress f3r an arbitrary rail temperature varies from 20 to 50 degree Celsius.

• 한국가금학회지
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• 제43권1호
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• pp.31-38
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• 2016

Consumers demand fresh and high-quality eggs. Egg quality may be represented by shell color, shell weight, egg weight, shell thickness, shell density, albumen height, yolk color, albumen pH and viscosity. Various factors such as strain, age of hen, storage temperature, humidity, the presence of $CO_2$ and storage time affect egg quality. Therefore, we investigated the effects of storage time and temperature on egg quality to define the freshness of Korean market eggs. A total of 1,800 eggs were used for this experiment and were separated into 45 treatments with 40 eggs in each. The treatments were consisted of 15 storage periods (2 d to 30 d) and 3 storage temperatures ($2^{\circ}C$, $12^{\circ}C$, $25^{\circ}C$). Each egg was weighed and broken, and the height of the thick albumen, Haugh units (HU), egg shell color and yolk color were measured by a QCM+system. We also observed the physiochemical properties of eggs such as yolk pH, albumen pH and albumen viscosity. The egg weight, shell weight, albumen height, HU and albumen viscosity significantly decreased with increasing storage time and temperature. However, the albumen and yolk pH significantly increased with increasing storage period and temperature. The interaction effects between the storage period and temperature were significant for shell weight, shell density, egg weight, albumen height, HU, yolk color, yolk pH, albumen pH and albumen viscosity. In the analysis of the correlation with egg quality, the storage temperature exhibited a higher correlation coefficient than the storage period. In conclusion, storage time and temperature are the major factors affecting egg quality, but the storage temperature is a more sensitive determinant of egg quality deterioration compared with the storage period.

• Journal of Acupuncture Research
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• 제21권1호
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• pp.119-135
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• 2004

Objective: The purpose of this study is to investigate the mechanism and effect of moxibustion with salt objectively, to be used as the quantitative data through the measurement of temperature, and to grasp the thermodynamic characteristics of moxibustion with salt. Methods: We have selected of the moxibustion with salt of indirect moxibustion. We make a comparative study of the thermodynamic characteristics of moxibustion with salt as a kind of the 4 salt. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa. Results: 1. We make out that it is not significantly change the time of thermal conduction of moxibustion with salt as a kind of 4 salt. 2. The heating period of Refined Salt was long and that of Sun-dried Salt was a short time respectively. The heating period of maximum tamperature is high Sun-dried Salt, Mechanical Salt and Refined Salt orderly. Maximun heating speed in the heating period was $0.151{\sim}0.184^{\circ}C/sec$ and at the same tendency of the maximum temperature in the heating period. 3. The retaining period was shorter than the heating period respectively, that is 15~24% of the combustion time of in the heating period. We make out that it is not significantly different the time of the retaining period as a kind of 4 salt. The mean temperature of retaining period was $43.2{\sim}48.1^{\circ}C$, that was extraordinarily high temperature. 4. We make out that it is not significantly different the time of the cooling period as a kind of 4 salt. The cooling period was measured 223~233sec. Beacuse the same density and size of moxa combustion was made an experiment. 5. The effective combustion time of Refined Salt is longer(259sec) than that of Sun-dried Salt(173sec). It is significantly different the time of the combustion time as a kind of 4 salt. 6. It is significantly different the Sample deviation of the combustion time as a kind of 4 salt because of the water content of the 4 salt individually. Conclusions: As the base on this study, we obtained the conclusion as the follows. The salt of moxibustion with salt was fitted for Sun-dried Salt due to making to Mechanical Salt recently. The Refined Salt is composition rate to another and small size comparatively. So It was fitted for the salt of moxibustion with salt. It is necessary to study continuously about the more suitable moxibustion with salt and quantitative analysis about the moxibustion with salt.

• 한국어병학회지
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• 제27권2호
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• pp.85-89
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• 2014

Water temperature is a key environmental factor controlling the epizootics of viral diseases in fish. High water temperature is associated with the rapid spread of rock bream iridovirus (RBIV) disease and with high mortality of RBIV infected fish. Although protection of fish against iridoviral disease by active immunization has been reported, little information is available concerning whether fish survived from an epizootic of iridoviral disease can naturally acquire resistance against the viral disease. In the present study, we have demonstrated that juvenile rock bream, which survived from a natural epizootic of RBIV, acquired resistance against recurrence or reinfection of RBIV, and this resistance was established during the subsequent low water temperature period. Furthermore, the possible involvement of the adaptive humoral immune response in the resistance of the juvenile rock bream was suggested by in vivo neutralization experiment.

• 한국식품영양과학회지
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• 제26권5호
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• pp.800-806
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• 1997

Effect of temperature on Kakdugi during fermentation was investigated by measuring sensory, physicochemical and microbiological, properties up to 57 days. The diced(2.5$\times$2.5$\times$2.5cm) Chinese radishes(Ra-phanus sativus L.) with other ingredients were fermented under the different temperatures. Kakdugi were stored at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 12 hours(treatment E) from initial fermentation to the end at each temperature on preparation. The pH was decreased to the range of 4.14~4.29 in the initial of pH 5.8, and total acidity was increased 2~4 times more than that of in the initial period (0.24%). And the changes of treatment A, B, and C were nearly constant up to 57 days in the range of 0.80~0.88% (pH 4.1). The changes of vitamin C showed sigmoidal curve, increasing significantly in the palatable period after decreasing gradually in the initial period. The content of vitamin C in treatment E was rapidly decreased, but that of treatment C was kept high content up to 57days. the number of lactic acid bacteria was remarkably increased in palatable period and was gradually decreased thereafter. The scores of aroma, taste, overall acceptability in sensory evaluation during the fermentation was high in order of treatment E, C, D, B and A. The scores of sensory evaluation treatment D and E during fermentation was rapidly decreased, however, treatment A, B and C were maintained. Changes of lactic acid bacteria, and sensory properties, among treatment A, B and C which kept a good quality up to 57 days, had high scores of sensory evaluation, abundant vitamin C in the palatable period. The result showed that Kakdugi fermented at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 36 hours had better taste and quality than those of other treatments.

• 생물환경조절학회지
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• 제9권2호
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• pp.115-119
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• 2000

표고버섯은 담자균류 송이과에 속하는 식용 버섯으로, 영양 성분 및 약리적 효능이 높기 때문에 동양인에게 중요한 버섯이며, 점차로 생산량과 소비량이 증가하고 있다. 본 연구에서는, 고품질 표고버섯 생산시기의 기상자료를 분석하여 표고버섯의 품질에 영향을 주는 생육 환경요인을 분석하였다. 이를 위하여 1997~1998년 국내 고품질 표고버섯이 생산되는 지역중 3지역(부여, 원주, 장흥)을 선정하였다. 표고버섯의 다량 발생시기 20일 기준으로 기상분석시기 15일을 선정하였다. 환경요인으로는 발생시기의 일 온도차, 일습도차, 일평균온도, 일 평균습도 및 풍속을 분석하였다. 발생기간중의 일 평균온도는 버섯 발생 온도 하한치인 $7^{\circ}C$ 이하에서 적정온도 $20^{\circ}C$까지의 변화를 보였고, 일 온도차는 주간에는 $7~20^{\circ}C$, 야간에 $0~-2^{\circ}C$의 범위를 나타냈다. 일평균습도 50~70%으로 강우에 따라서 변화 폭이 컸으며, 일습도차는 40~60%의 차를 나타냈다. 풍속은 1~4m.$s^{-1}$이었다 .따라서 화고, 동고의 생육환경은 일반적인 표고버섯의 적정 생육 조건과는 큰 차이를 보였다. 생육기간동안의 일 온도차, 일습도차, 저 습도, 풍속 등의 환경 조건은 고품질 표고버섯 발생의 요인의 하나라고 추정된다. 이 연구결과는 버섯의 시설재배시 고품질 표고버섯 생산을 위한 환경조절기술로 적용될 수 있을 것으로 판단된다.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2001년도 봄 학술발표논문집
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• pp.43-44
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• 2001

Recently the sawdust culture of Lentinus edodes(Berk.) has been gradually extended replacing the log cultivation in Korea. It is indeed able to reduce the use of log and cultivation period in controlled facilities, but is not yet able to produce the high-quality mushroom. The objectives of this study were to examine the effects of low and alternated temperature treatments during the fruiting period on the quality of oak mushroom. At low temperature treatments of 1$^{\circ}C$ and 10$^{\circ}C$, the crack, lightness, hardness, and other characteristics for the high-quality oak mushroom were not improved. However, the crack, brightness, and hardness of cap were increased at alternated temperatures of 5-10$^{\circ}C$ than the other temperature treatments. In conclusion, the alternated temperature treatments were more effective than the low temperature treatment for improving the indices of high-quality oak mushroom such as the crack, brightness and hardness of cap.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.43-43
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• 2017

During grain filling period, rice is affected by many environmental factors; including temperature, water, radiation and soil nutrition condition. In future climate, greater shading and heat tolerance will be required in rice. In this study, the effect of shading and high temperature on spikelet sterility was conducted on fourteen Vietnamese cultivars. Field experiments were studied in 2015 and 2016 to evaluate the response of Vietnamese cultivars under high temperature during grain filling stage. The high temperature and shading were applied by closing two sides of growth chamber and covered by a black cloth (50% reduced solar radiation) under the field condition after the first cultivar heading. The sterility increased significantly under high temperature and shading. The highest percentage sterile spiketlets was observed in 'Jasmine 85' (71.7%) under shading and in 'OM4900' (53.4%) under high temperature in 2015 and 2016, respectively. Among the treatments, the percentage of sterile spekelets in Vietnamese cultivars under shading was highest which was 54.9% and 41.8% in 2015 and 2016, respectively. Yield components reduced significantly in both of shading and high temperature. Corresponding with significantly decrease in yield components, the yield in high temperature and shading decreased strongly in both 2015 and 2016.

• Fisheries and Aquatic Sciences
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• 제26권2호
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• pp.117-132
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• 2023

Chum salmon (Oncorhynchus keta) is a species of anadromous salmonid inhabiting coastal rivers in the North Pacific and the Arctic in the Bering and is the most widely distributed among Pacific salmon species. It is an important fish species in Korea as the salmon releasing project is being actively carried out. This study was conducted to investigate changes in the physiological activity of O. keta according to water temperature. Three experiments were conducted according to the water temperature and period, and the plasma concentrations of cortisol and glucose were analyzed from the blood samples of the experimental groups. Experiment I is a short-term water temperature experiment, in which water temperature stimulation was given for 4 hours at water temperatures of 12℃, 16℃ (control), 20℃, and 24℃, and a recovery period was given for 4 hours. Experiment II is an experiment in which water temperature stimulation was given for 24 hours, 48 hours, and 72 hours at a high temperature of 24℃, and a recovery period was given for 12 hours, respectively. Experiment III is a long-term water temperature experiment, in which the water temperature was 12℃, 16℃ (control), 20℃, and 24℃ for 8 weeks. As a result of the experiment, in Experiment I, there was no significant difference in the survival rate between the experimental groups, but the concentration of cortisol and glucose in the plasma according to the set water temperature showed a significant difference. In Experiment II, there was no significant trend according to the maintenance time of the high-temperature state, but as the temperature increased, the plasma cortisol and glucose levels significantly increased compared to the control group. In Experiment III, all of the experimental group C (24℃) died in the 1st week, and there was no significant difference in the plasma glucose at the 1st and 8th weeks among the remaining experimental groups.