• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.500-512
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• 2009

This study was carried out to evaluate the effect of temperature on soil microbial biomass, enzyme activities, and PLFA content in the volcanic(VAS) and the non-volcanic ash soil(NVAS). The soils were treated with organic materials such as organic fertilizer pelleted(OFPL), organic fertilizer powdered(OFPD), pig manure compost(PMC), and food waste compost(FWC). Two grams of organic materials were well mixed with 30g of dried volcanic and non-volcanic ash soil(< 2 mm) with 50% of soil moisture content. And the soils were incubated at 10, 20, $30^{\circ}C$ in incubator. Soils were analysed on the incubation times as followed; soil pH, total nitrogen, organic matter(at 75, 150, 270 days), microbial biomass C and PLFA (at 75, 270 days), microbial biomass N and soil enzyme(at 150, 270 days). pH values of soils treated with PMC and FWC had no changes on soil type, and incubation temperature. However, the pH was increased with temperature in the soils treated with OFPL. The changes in NVAS was higher than in VAS. Soil microbial biomass C content were high in the condition of high temperature and organic fertilizers treatment in VAS. But the contents were gradually decreased with incubation period in both NVAS and VAS. Soil microbial biomass N was high in NVAS treated with organic fertilizers and in VBS treated with PMC and FWC. PLFA content was higher in NVBS than in VBS at 75 days but showed high in VBS at 270 days. Urease activity of NVBS treated with OFPL showed $10^{\circ}C$ (75.0)> $20^{\circ}C$ (16.3)>$30^{\circ}C$ ($4.6ug\;NH{_4-}N\;g^{-1}\;2h^{-1}$) at 150 days. It were decreased gradually high temperature and time passes. And it showed high at $10^{\circ}C$ in VBS. Glucosidase activity was higher in NVBS than in VBS. Correlation coefficient of between soil microbial biomass C and microbial activity indicators showed that PLFA was high significantly at $r^2=0.91$ in NVBS and ${\beta}-glucosidase$ was $r^2=0.83$ in VBS. Soil microbial activities showed differences in the relative sensitivities of soil type and soil temperature.

• Journal of the Korean Society of Food Culture
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• v.35 no.5
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• pp.450-458
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• 2020

This study examined the optimal temperature and time conditions to maintain high quality Dongchimi during the fermentation and storage period. Dongchimi was fermented at low (5℃), medium (10 and 15℃), and high (20℃) temperatures until the acidity reached 0.2, 0.3, and 0.4%. respectively. From the consumer's preference test enrolling five consumers, Dongchimi fermented at 15℃ until an acidity of 0.3% (for approximately six days) was evaluated to be the optimal status because of its high score of overall acceptance, taste, and odor of consumers. To determine the optimal storage temperature of fermentation, Dongchimi was stored at three different temperatures (-1, 2, 5℃) for four weeks after fermenting at 15℃ for six days. During the storage period, most of the physicochemical properties (pH, acidity, reducing sugar content, and organic acid) and microbiological properties changed significantly in the 2 and 5℃ groups, resulting in a significant change in descriptive sensory analysis of Dongchimi. These results indicate that fermentation at 15℃ and storage at -1℃ for Dongchimi enables it to maintain the best quality for a long time.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.251-257
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• 1975

In order to investigate the effects of high ambient temperature on the thyroid, a total of 50 rabbits (mean weight, 1,294g) reared under $7^{\circ}C$ were alloted to two groups. Rabbits in one group served as controls and the others, after reared under $30^{\circ}C$ for 16 days, were returned to the normal temperature for 16 days. The results obtained in this work were summerized as follows: 1. The weight of the thyroid gland was decreased severely from the 2nd day and increased to normal range on the 4th day after returned to normal temperature. 2. Thyroid follicles were atrophied significantly from the 1/2 day and then enlarged gradually from the 4th day, while their colloid substance also manifested poor staining, coagulation, and disappearence, being reappeared from the 8th day. 3. Hypertrophied follicular epithelial cells showed more enlarged size, degeneratien, necrosis, and mitosis from the 1/2 day in accordance with experimental term and those changes were diminished from the 8th day. 4. Histologically thyroid manifested-hypothyroidism on the 16th day but showed mild hyperthyroidism on the 2nd day and euthyroidism from the 4th day of returned roaring.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.641-644
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• 2008

The strength of concrete is developed by cement hydration reaction influenced by the circumferential temperatures. In this study, therefore, the experiments are conducted and evaluated about the characteristics as changes of early concrete placing temperature and curing temperature to understand the effects of the temperature which influences concrete properties. The results of the experiments changing the early concrete placing temperature in 5$^{\circ}C$ and 10$^{\circ}C$ are followed. In case of conducting standard concrete curing, early compressive strength development rate of the concrete which had low placing temperature was low, but it was shown that early compressive strength development rate was not affected by low placing temperature in age 28 days of concrete. In case of conducting outdoor curing in winter, early compressive strength development rate of the concrete which had high placing temperature was high in all test specimens. As a results, early compressive strength development of concrete was influenced by temperature of early concrete, but after aging 28 days of concrete, it was influenced by curing temperature rather than temperature of early concrete.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.2
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• pp.79-84
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• 2015

Pre-drying of 'Fuyu' persimmon was performed right after harvesting from a farm. Pre-drying conditions were varied with room temperature (RT) for 1 day to 7 days, low temperature (LT, at $20{\sim}30^{\circ}C$) for 1 day to 4 days, high temperature (HT, at $30{\sim}40^{\circ}C$) for 3 h to 12 h, and ultra-high temperature (UT, at $50{\sim}60^{\circ}C$) for 30 min to 120 min. Weight loss of pre-dried persimmon was increased from 1.62% up to 2.96% with increased pre-drying temperature and time. Pre-drying at RT resulted more significant weight loss of persimmon compared to that of pre-drying at HT. Minimum firmness loss of persimmon stored at $0^{\circ}C$ for 100 days was obtained at the condition of HT for 6 h. Rate of peel blackening was decreased from 31.5% to 16.4% and 10.9% by pre-drying at HT for 6 h and 9 h, respectively.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.193-200
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• 2008

We obtained quantitative information on leaf unfolding and leaf shedding by observing 45 species of cool temperate deciduous trees in an arboretum over 5 growing seasons. These trees were in leaf (the foliage period) for 207 days on average after 1 April; 50% of leaves had been shed by 192 days after 1 April. Duration from the start of leaf unfolding to 50% leaf shedding was 157 days on average. Leaf unfolding began 35 days on average after 1 April. For leaf unfolding to begin, a$ 51^{\circ}C{\cdot}day$ of cumulated daily mean air temperature above $5^{\circ}C$ from 1 January (modified Kira's warmth index) was needed. Fifty-nine days elapsed between initiation and the final stage of leaf unfolding. The period of net photosynthetic assimilation was 157 days. The species with succeeding- type leaf unfolding associated with the anemochore seed type dominated the early stage of succession, while the species with flush-type leaf unfolding tended to dominate the late stage of succession. Few species were found in regions where late frosts occur after the day when the cumulative temperature for leaf unfolding is achieved. Biological characteristics include time of leaf unfolding, which affects the life history of each species, so that each species occupies its own niche in the stand. We conclude that that leaf phenology, such as timing of leaf unfolding and leaf shedding, is one of the components of each species' ecological characteristics.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.1
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• pp.65-68
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• 2005

Growth and development of a plant over a growing season is closely related to the daily accumulation of heat. Heat unit measured by accumulated growing degree days (GDD) is becoming increasingly popular to estimate the growth of a plant or even in insect. GDD or heat accumulation per day is measured by calculating average daily temperature and then subtracting the base temperature below which growth does not occur. Heat accumulation per day is added for the desired period and accumulated GDD is determined. The present study was conducted in five seasons in an established garden with K-2, S-36 and V-1 mulberry varieties belonging to Morus indica L. grown under completely irrigated condition at the farm of CSRTI, Mysore during 2001 - 2002. Plants were pruned in each season and the growth of the plant measured by total shoot length and fresh leaf yield was recorded at an interval of 5 days starting from 30 days of pruning (DAP) to 70 days when all the plants were pruned. The accumulated GDD for the corresponding days were recorded and used for analysis. Accumulated growing degree days (GDD) have been found to be perfectly correlated with both growth and yield in all the seasons in all the varieties studied. The high $R^2$ values indicated a strong relationship between the accumulated GDD and, growth and yield of mulberry.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.05a
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• pp.141-145
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• 2008

In this paper, non working day for the construction project in Cheongju region considering weather condition for 30 years from 1971 to 2000 and 10 years from 1991 to 2000 as statistical periods was estimated. In Cheongju region, there was no remarkable difference between them because non working day for outside and half outside work was 157days and for interior work 144days at statistics for 30 years., and utside and half outside work was 159days and for interior work 142days at statistics for 10 years.. However, non working day due to high temperature is slightly increased, and non working day due to cold weather is slightly decreased in the case that the recent statistical data was used caused by global warming. Non working day due to rainfall was 23 days at statistics for 30 years, and it was 28 days at statistics for 10 years.

• Korean Journal of Poultry Science
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• v.24 no.1
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• pp.1-8
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• 1997

The effects of genetic, physiological, and environmental factors(temperature, and type of watering system) on growth factors, accumulation of abdominal fat(AF), and the association between growth factors and AF of broilers and Athens-Canadian Randombred (ACRB) were studied in a series of nine trials. The final BW(6 or 7 wk) and 4-6 or 5-7 wk gain (G) were greater in groups raised at 21.1˚C than 26.7˚C. There was no consistent effects of environmental temperature on feed conversion ratio (FCR) although the FCR was significantly (P$\leq$.o5) reduced in 21. 1˚C group compared with the 26.7˚C group in two of six trials. The overall mean weight of AF relative to BW at 43 or 50 days of age were not significantly different between temperature groups: the means of AF of 21.1˚C and 26.7˚C groups were 1.81 and 1.78%, respectively. Environmental temperature had no consistent effect on the relationship between 4-6 or 5-7 wk C and 43 or 50 days AF, and 4-6 wk FCR and 43-days AF ; however, the association of 50 days AF with 5-7 wk FCR was highly significant in both temperature groups. The overall mean of correlation coefficient between FCR and AF was very low (r=.107). The waterer types did not significantly affect the AF. Generally, the effect of sex on the relationship between G and AF was not consistent in both sex groups. However, the association of AF with G was much greater in ACRB group compared with broiler group. The initial body weights (4 or S wk) was significantly (P$\leq$.001) correlated with AF in ACRB group, but not in the broiler groups. The effect of sire on AF was very high(P$\leq$.0001) in five of six trials.