• Korean Journal of Construction Engineering and Management
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• v.6 no.1 s.23
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• pp.58-64
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• 2005

We should consider climatic factors influencing construction works in order to estimate construction time correctly. This study is to analyze climate elements affecting construction duration and to calculate non-working days far Inchoen territorial region. Through surveying literatures and examining several existing criteria we suggest a Proper criteria for each climate elements which would be used for estimating non-working days. The criteria is made on the raw climate data of Meteorological Administration during the last 30 years(1974-2003) far Incheon region. In case of rainfall, it is estimated as non-working days when daily precipitation is expected more than 10mm, its number of days for Incheon is 29 days. In case of low temperature, the number of non-working days for the concrete works(its criteria be below $4^{\circ}C$ average) and the finishing works(below $0^{\circ}C$ average) is 97 days, 52 days, respectively. In case of high temperature, it is three days when daily highest temperature is expected going over $32^{\circ}C$

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.2
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• pp.41-46
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• 2000

This experiment was carried out to find out the responses of the growth characteristics to various air temperature in a high yielding indica/japonica rice cultivar, 'Dasanbyeo'. Five different transplanting dates with 30 day-old seedlings were tried to induce various environmental conditions, starting from 10th May to 19th June in the interval of 10 days at National Crop Experiment Station, in 1998. Planting densities with different plants per hill but same hill spacing were tested. The daily mean air temperature during 30 days after transplanting was 19.0, 20,8, 21.9, 24.4 and 25.2$^{\circ}C$ when transplanted on the 10th May, the 20th May, the 30th May, the 9th June and 19th June, respectively. The number of tillers per hill at 30 days after transplanting was affected by the daily mean air temperature during 30 days after transplanting. The higher the daily mean air temperature, the more tillers per hill at 30 days after transplanting were. The growth duration from transplanting to heading was greatly changed according to the transplanting dates. It was shortened as the transplanting date was delayed until transplanted on the 9th June, but it was prolonged when transplanted on the 19th June compared to that of the 9th June. The number of panicles per hill increased with the increase of the transplanted plants per hill up to 7 plants per hill. The number of panicle per unit area was closely related to the number of tillers per unit area at maximum tillering stage. It was found that the average effective temperature during first 10 tiller formation related to the days to the tenth tiller formation with the relationship of y = 1.071x$^2$ - 37.307x + 342.38($R^2$ = 0.9823).

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.2
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• pp.33-40
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• 2000

Dispersion of high temperature and high salinity water discharged from a desalination plant is numerically estimated to investigate its impact on marine environment. The plant is installed on a floating barge located in Jinhae Bay and takes 200 tons of seawater per day. Fifty tons of intake are changed into fresh water, while 150 tons of those are discharged as the water of 15℃ warmer and 1.33 times saltier than surrounding seawater. In this dispersion model, advection is described by two-dimensional tidal currents and turbulent diffusion is simulated by Monte Carlo technique. Decay of water temperature is modelled by heat exchange between the atmosphere and the ocean, while decay of water salinity is ignored. The distributions of temperature and salinity come to equilibrium when the dispersion model is run for 100 days for temperature and for 365 days for salinity, respectively. At equilibrium state the water temperature and salinity rise 0.01℃ and 0.001‰ higher than ambient seawater, respectively.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.434-441
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• 2010

'Wonhwang' pear ($Pyrus$ $pyrifolia$ Nakai) often showed physiological disorder and quality deterioration during long-term storage and shelf life although this cultivar has the advantage of a good appearance and better taste for overseas exportation. This study was conducted to investigate the effect of temperature during transportation and continuing market temperature on fruit quality, and the occurrence of physiological disorder to set up the appropriate transportation and distribution temperatures in the fruits harvested at different times. Unripe fruits harvested 120 days after full bloom maintained higher firmness until 21days of shelf life at both 18 and $25^{\circ}C$ than late harvested ones. Otherwise, ripe fruits harvested 130 days after full bloom showed high incidence of mealiness breakdown of flesh tissues in 21 days of shelf-life at $25^{\circ}C$ of market temperature, but not in the fruits stored at $18^{\circ}C$. Late harvested fruits showed much severe physiological disorders when compared with early harvested ones that showed relatively lower respiration rates. Fruit quality parameters were more highly affected by market temperature than transportation temperature. Results showed that unripe fruits harvested at 120 days after full bloom maintains high marketability until 21 days of shelf-life, while the maximum shelf-life of ripe fruits harvested 130 days after full bloom will be considered at within 7 days.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.283-288
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• 2006

Characteristics of the rootstock formation and flower bud differentiation according to sowing time for production of the high quality rootstock in Chicory (Cichorium intybus L.) was investigated. The flower bud initiation was on the 17th of July after sowing in April, the 2nd of July after sowing in May, the 30th of July after sowing in June and the 1st of October after sowing in July. But they didn't differentiate after sowing in August and September. The days required from germination to flower bud initiation and accumulated temperature depended on the weather. If the outside air temperature was high, the days required were less, If the outside air temperature was low, the days required were greater, the accumulated temperature was similar to the days required in this experement, too. The rootstock sown from April to July wasn't good enough to be use because the flower bud differentiation was generated before harvestable weight. the weight of rootstock was sown in September wasn't heavy enough in weight because the outside air temperature was too low for it to grow well. The plant grows slow and steady through out winter. The rootstock sown in August was havestable 200g in 90 days after sowing before the flower bud differentiated. The best sowing time for the production of high quality rootstock of Chico in the climate of Korea is researched to be August.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.4
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• pp.343-349
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• 1988

In order to get informations for breeding early barley cultivars, the thermosensitivity and low temperature growth ability about the breeding materials vernalized were tested at the high '||'&'||'amp; low temperature and field conditions. The temperature coefficient (Q10), ratio and thermosensitivity for plant height were various among cultivars versus temperature treatments. The early cultivars had greater Q10 values and insensitive responses to temperature changes. The Q10 and thermosensitivity for the time of flag leaf unfolding were various among cultivars, but the coefficient of variation in the thermosensitivity was greater, so the character would be more useful for investigating the varietal differences. The Q10 and thermosensitivity for plant height were not significantly correlated with Q10 and thermosensitivity for the time of flag leaf unfolding. The periods from heading to flowering were 2 to 4 days at the high temperature plot, but 1 to 11 days at the low temperature plot, showing much greater variations. In general the cultivars with greater difference of heading time between the high and low temperature plots were Suwon 218, SB 76588, Oweolbori, and Jogangbori, showing the sensitive thermophase and early heading.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.599-602
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• 2005

In this research, the characteristics of the strength development and chloride attack resistance on the concrete using high early strength cement by steam curing temperature condition were studied. As a result, It is observed that the early strength(16hr) is increasing and the strength of 28 days is decreasing, according as the rising of the steam curing temperature without the kinds of base cement(OPC and high early strength cement). On the other hand, it is observed that the more the contents of the unit binder(base cement + GGBF) is abundant, the more the steam curing temperature can be reduced in case of the high early strength. Also, the chloride attack resistance is improved according as the amount of GGBF is increased with the kinds of base cement(OPC and high early strength cement).

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.203-204
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• 2016

In this research, it used cement power and reduction slag, which generates high hydration heat in hydration reation without heat cure below -5℃ degree. Purpose of final research is preventing freezing and thawing by making the compressive strength 5MPa in 3days below zero temperature due to own heat of concrete. and it is the result of physical characteristic and thermal property evaluation of reduction slag. Because reduction sag generates high hydration heat, compressive strength development is excellent. By generating highly Hydration heat by C₁₂A₇ and C₃A in reduction slag, compressive strength is developed in low temperature. In case of displacing only reduction slag without SO₃, it is indicated that quick-setting occurs by shortage of SO₃. For preventing quick-setting, gypsum is used essentially. According to this research result, in case of using reduction slag and gypsum as a ternary system, Compressive strength developed 5MPa in 3days below zero temperature. It is identified to prevent early frost damage of concrete below zero temperature.

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.147-157
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• 1997

It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.439-444
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• 1983

Effects of temperature and soil moisture on the growth and grain-filling of two wheat cultivars were investigated. Two levels of temperature; day 3$0^{\circ}C$/night $25^{\circ}C$ and day 2$0^{\circ}C$/night 15$^{\circ}C$ and two levels of soil moisture; stressed (45-50% of F.C.) and non-5tressed (50-60% of F.C.) were imposed in the green house from heading date to the maturity and grain weight, chlorophyll content of flag leaf and leaf area index(LAI) were observed at weekly interval. Grain maturation was faster in the high temperature than those in the lower temperature. Chlorophyll content of flag leaf and LAI decreased rapidly in the high temperature and chlorophylls disappeared at the 20 days after heading. In lower temperature condition, slower decrements were shown in chlorophyll content and it remained until 45 days after heading. Grain weights in the high and optimum temperature conditions reached to maximum values at 29 days and 45 days after heading, respectively. Differences of grain weight and chlorophyll content of flag leaf were not significant between stressed and non-5tressed soil moisture condition.