• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.24-33
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• 1989

This study was conducted to investigate the effect of paclobutrazol [(2 RS , 3 RS )1-(4- chlor-ophenyl )-4, 4- dimethyl -2- (1, 2, 4- triazol -1- yl )- pentan -3-01] on the tolerance of hi-gh temperature and drought stress as related to growth retardation , iranspiration rate , soil water content , nitrogen level and photosynthetic rate in perennial ryegrass ( Loliurn perenne L . ' Omega H , ). Plants were given a 30 ml soil drench of paclohutrazol at the concentrations of 0, 0.01, 0.1, 1.0, 10.. 0, mg / 6 .5cm- diameter pot . The rcsults were as follows : 1. Increasing concentrations of paclohutrazul reduced plant height , leaf area , fresh weight and dry weight , hut increased chlorophyll content per unit area . The number of tillers and leaf width were not affected hy the paclobutrazol concentrations . 2. The proper concentration of paclohatrazol on growth retardation in perennial ryegrass was about I mq /pot , hut leaf deformity and severe growth retardation were shown at high concentration of 10 mq / pot . 3. Perennial ryegrasses grown at 30˚C were shown significantly short plant height and low leaf nitrogen level compared with those grown at 20˚C. Increasing concentrations of paclohutrazol at 20˚C increased nitrogen level hut it could not increase nitrogen level at 30˚C . 4. During the drought stress , increasing temperatures significantly promoted transpiration rate and wilting time . It took about 5 days at 20˚C and 3 days at 30˚C to reach wilting time of leaves from water stress treatment . Soil water contents at wilting time of non-treated controls were averaged 6. 871% at 20˚C and 6. 17% at 30˚C 5. Paclohutrazol reduced transpiration rate at high temperature and drought stress . Wilting appeared at the lower water content of soil according to increasing concentrations of paclobutrazol at 30˚C hut there were no differences among concentrations of at 20˚C. 6.Paclohutrazol treatment at 1 rag /pot reduced injury rate of leaves from 67.1 % and 100 % in control plants to 15.7% and 80% at 20˚C and 3010, respectively. 7. Photosynthetic rate per unit area was significantly reduced at high temperature . Paclohutrazol stimulated photosynthetic rate with increase of concentrations at 20˚C but there was no increasing effect at 30˚C.

• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.463-477
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• 2003

This study identified the effects of global temperature rise on snowfall change over Korea selecting Seoul, Gangneung, Gunsan, and Daegu as study areas. The trend of snowfall change has generally decreased since 1950s over Korea, but has only increased in Gunsan since 1990s. The variation of snowfall days are similar to those of snowfall. The relationship between snowfall over Korea and the anomaly of global mean temperature in spring has a negative correlation. The change of Siberian High intensity also has a good relationship with snowfall in both Gunsan and Gangneung; the former is positively correlated while the latter is negatively correlated. This result might suggest that if the intensity of Siberian High would weakens due the ongoing global warming in the future, there would be a possibility that the amount snowfall could decrease in Gunsan but it could increase in Gangneung.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.7-14
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• 2003

A series of laboratory tests, which can show how different curing conditions influence an aging effect on clay, were carried out for the clay samples collected in the area of Kwangyang Bay and Mokpo. Clay samples were remolded and reconsolidated under three different curing temperatures (20, 50, and 80 degree Celsius) and low different curing durations (1, 7, 14, and 40 days). To find out an aging effect and geotechnical characteristics between undisturbed samples and reconsolidated samples, laboratory tests, consisting of uniaxial compression tests, CU triaxial test, and consolidation tests, were preformed. Results showed that the compression index ratio is very useful factor to indicate the aging effect of natural clays. Also geotechnical characteristics of clays reconsolidated at high temperature were very similar to those of undisturbed clays. Finally, curing temperature and curing duration influenced an aging effect on clays. The best curing condition was 80 degree Celsius and 27 days.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.49-69
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• 1988

In order to develop a cropping system that can produce garlic in the period of short supply from March to April, effects of low temperature treatment of seed bulbs and planting dates, starting date of low temperature treatment, days of low temperature treatment on plant growth, maturity and yield were studied in Southern strain, 'Namhae' and in Northern strain, 'Euiseong' of garlic (Allium sativum). The results obtained were as follows. In Sorthern strain, sprouting was significantly enhanced by low temperature treatment only in Sep. 14, and Sep. 29 plantings. Days to sprout were least in 30 days of low temperature treatment of Sep. 14 planting and in 45 days treatment of Sep. 29 planting. When considering on the beginning date of low temperature treatment, a marked difference was observed between treatments started before July 31 and after Aug. 15. Sprouting was most enhanced in 45 days low temperature treatment of Aug. 15 and Aug. 30 plantings. In Northern strain, sprouting was en hanced by low temperature treatment in planting from Sep. 29 to Nov. 13 and low temperature treatment for 60 days was most effective. Effect of low temperature treatment on early plant growth was observed in Sep. 14 and Sep. 29 plantings, but the effect on plant growth at intermediate stage or thereafter was observed in up to Oct. 29 plantings. Optimun days for low temperature treatment on growth enhancement was 45 and 60 days in Southern strain and 60 days in Northern strain in each planting dates. In Southern strain, the longer the low temperature treatment and the later the planting date the less the number of leaves developed. In Northern strain, normal leaves were not developed in plantings from Sep. 14 to Nov. 13. In Southern strain, clove differentiation and bulbing were earlist in 45 and 60 days treatment of Sep. 14, Sep. 29, and Oct. 14 planting initiated on July 31 and Aug. 15. In Northern strain, clove differentiation and bulbing were earlist in 60 days treatment of Oct. 14 planting initiated on Aug. 15 and Aug. 30. In treatment initiated later than above, longer the low temperature treatment the earlier the clove differentiation and bulbing in both Southern and Northern strains. The earlier the initiation date and the longer of low temperature treatment, the earlier bolting in southern strain. In Northern strain, bolting was most enhanced in 45 and 60 days of low temperature treatment initiated on Aug. 15 and Aug. 30. The longer the low temperature treatment in plantings thereafter, the earlier the bolting. The earlier the planting date garlic bulbs. Harvest date was earliest in 45 and 60 days low temperature treatment started from July 31 to Aug. 30 in Southern strain, and it was in 60 and 90 days low temperature treatment initiated from July 31 to Aug. 30 in Northern strain. Bulb weight was heaviest in 45 days low temperature treatment of Oct. 14 planting and next was in 45 days treatment of Sep. 29 planting in Southern strain. In Northern strain, bulb weight was heaviest in 60 days treatment of Oct. 14 planting and next was in 45 days treatment of Oct. 14 planting. When considered in the aspect of the beginning date of low temperature treatment, bulb weight was heaviest in 45 days treatment started on Aug. 30 in Southern strain and in 60 days treatment started on Aug. 15 in Northern strain. A high negative correlation between days to harvest and plant height on January 12, and a high positive correlation between days to harvest and days clove differentiation were observed. This indicates that enhanced plant growth and clove differentiation induced by low temperature treatment advanced the harvest date. A high negative correlation between bulb weight and days to clove differentiation, days to harvest suggests that the enhanced clove differentiation result and in heavier bulb weight. From the above results, it suggested that early crop of garlic can be harvested by planting at the period of Sep. 29 to Oct. 14 after 45 days of low temperature treatment of seed bulbs of Southern strain. Then harvest date can be shortened by 30 days compared to control and garlic can be harvested in early April.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.2
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• pp.93-100
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• 2011

The study was conducted to investigate the correlation analysis between fruit quality and climatic parameters in grapevines. 'Campbell Early', one of the major grape cultivars, occupies more than 70% of cultivated areas in Korea. Recent research results have shown that the movement of cultivation area of fruit production resulted from the temperature increase. In this study, we investigated the relationship between fruit quality and climatic conditions in 13 major 'Campbell Early' grape producing areas (i.e., Sacheon, Jinju, Naju, Dangjin, Cheonan, Gimcheon, Yeongdong, Okcheon, Sangju, Suwon, Yeongju, Gangneung, Chuncheon, and Yanggu). The earliest and latest full blooming days of grapevines were ovserved on May 25 in Sacheon area and on June 7 in Yanggu area, respectively. At least 90 days are required for grapes to mature enough for the production of highquality fruits. The southern areas with less than 90 days of maturity period had difficulty in the production of good fruit. However, the areas with longer maturity period of 100 to 110 days produced grapes with with high sugar content and good coloring. The fruit qualities of 'Campbell Early' grapes are more closely related with temperature than other climatic factors. High temperature resulted in fruits with high acidity and delayed the coloration of the fruit skin in the southern area. The fruit skin was thin in the southern area and inclined to be thicker in the northern areas. Therefore, grape should be cultivated in regions with long maturity period to have high quality.

• Computers and Concrete
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• v.24 no.1
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• pp.1-6
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• 2019

Within the scope of this study, the foam solution was prepared by properly mixing sulfonate based foam agent with water. Furthermore, this solution was mixed with the mixture of fine sand, cement, and water to produce foamed concrete. The mixture ratios which are the percentage of foam solution used in foam concrete were chosen as 0, 20, 40 and 60% by vol. After these groups reached 28 days of strength, they were heated to 20, 100, 400 and $700^{\circ}C$ respectively. Afterward, high-temperature effects on the foamed concrete were obtained by employing physical and mechanical properties tests. Additionally, SEM (scanning electron microscope) and EDX (energy-dispersive X-ray spectroscopy) tests were employed to analyze the microstructure, and ${\mu}-CT$ (micro computed tomography) images were used to reconstruct 3-D models of the heat-treated specimens. Then, these models are analyzed to examine the void structures and the changes in these structures due to the high temperatures. The study has shown that the void structures reduce the high-temperature effects and the foam solution could be mixed with concrete up to 40 % by vol. where the high strength of foamed concrete is non-mandatory.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.305-313
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• 2018

A microbial consortium, TMC7, was enriched for the degradation of natural lignocellulosic materials under high temperature. TMC7 degraded 79.7% of rice straw during 15 days of incubation at $65^{\circ}C$. Extracellular xylanase was effectively secreted and hemicellulose was mainly degraded in the early stage (first 3 days), whereas primary decomposition of cellulose was observed as of day 3. The optimal temperature and initial pH for extracellular xylanase activity and lignocellulose degradation were $65^{\circ}C$ and between 7.0 and 9.0, respectively. Extracellular xylanase activity was maintained above 80% and 85% over a wide range of temperature ($50-75^{\circ}C$) and pH values (6.0-11.0), respectively. Clostridium likely had the largest contribution to lignocellulose conversion in TMC7 initially, and Geobacillus, Aeribacillus, and Thermoanaerobacterium might have also been involved in the later phase. These results demonstrate the potential practical application of TMC7 for lignocellulosic biomass utilization in the biotechnological industry under hot and alkaline conditions.

• Journal of Environmental Science International
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• v.9 no.4
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• pp.295-302
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• 2000

This study was conducted to investigate the characteristics of surface ozone concentration and occurrence of high ozone concentration using hourly ozone, nitrogen dioxide and meteorological data for 1997~1998 in Pusan coastal area. Monthly mean ozone concentration was the highest at Dongsamdong in Spring(35.4ppb), at Kwangbokdong in Fall(25.1ppb) and the lowest Dongsamdong(22.2ppb) and Kwangbokdong(16.0ppb) in Winter. Relative standard deviation indicating clearness of observation site was 0.42 at Dongsamdong and 0.49 at Kwangbokdong that is similar to urban area. The diurnal variation of ozone concentration of Dongsamdong and Kwangbokdong showed maximum at 1500~1600LST and minimum 0700~0800LST that typical pattern of ozone concentration. In ozone episode period(Sept. 10~15, 1998), diurnal change of ozone concentration was very high, and ozone concentration was related to meteorological parameters such as temperature, relative humidity, wind speed, cloud amount and radiation on a horizontal surface. During the episode days peak ozone concentrations are much higher than the normal values, wind speeds are always lower, and solar radiation is high with the exception of the September episode.

• Journal of Food Hygiene and Safety
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• v.5 no.4
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• pp.219-228
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• 1990

Whey proteins in milk were analyzed by polyacrylamide gel electrophoresis and compared with respect to electrophoregrams, densitograms and concentrations of whey proteins in raw and market milk classified according to 3 kinds of pasteurization by low temperature long time. high temperature short time and ultra-high temperature short time. Relative composition of major whey protein constituents such as bovine serum albumin, ${\alpha}\;-\;lactalbumin\;and\;{\beta}-lactoglobulin$ in raw milk were 3.71:11.44:84.85 and not affected by low temperature long time and high temperature short time pasteurization, even though there were the tendencies of some declining in the actual concentrations. But by ultra-high temperature short time pasteurization compositions of whey protein were changed to 0: 64.75: 35 in which reflected the disapprearance of bovine serum albumin and the extensive decrease of ${\beta}-lactoglobulin$. Storage of low temperature pasteurized milk at $5^{\circ}C$ resulted in a slight decrease of ${\alpha}\;-\;lactalbumin\;a\;{\beta}-lactoglobulin$, but storage at $25^{\circ}C$ did not make any changes until3rd days of storage. Most of whey proteins in high temperature short time pasteurized milk were not affected during storage at $5^{\circ}C\;and\;25^{\circ}C$, but bovine serum albumin and ${\alpha}\;-lactalbumin$ diminished in 2-3 days of storage. Whey proteins of milk treated with ultra-high temeperature were not affected during storage at $5^{\circ}C\;and\;25^{\circ}C$ except a slight decrease of ${\alpha}\;-lactalbumin$ in 2nd day of storage at $5^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.49 no.2
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• pp.341-355
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• 2022

This research was to examine the differences in post-harvest quality of melons depending on the harvest time after fruit setting. Musk melon cultivar 'K3' plants were grown in glass house conditions with a hydroponic system, and the fruits were harvested at 50, 60, and 70 days after fruit setting. The post-harvest characteristics of melons stored at 7℃ were measured over 32 days. The harvested fruits at 50, 60, 70 days after fruit setting did not differ significantly in weight, height, or size. Solid sugar content was highest in the fruits harvested at 70 days after fruit setting, but firmness, L* value, and respiration rate were highest in the fruits harvested at 50 days after fruit setting. When the harvested melons were stored at 7℃, 'K3' melons responded differently according to the harvest days after fruit setting. The major changes during storage of 'K3' melons can be summarized as follows: Firmness, respiration, moisture content, and general appearance index during storage were highest in the melons harvested at 50 days after fruit setting, but soluble solid content, fresh weight loss, and sensory evaluation were high in the melons harvested at 60 and 70 days after one. During storage at 7℃, there were no significant differences in the appearance of 'K3' melons harvested at different periods after fruit setting, but difference in soluble solid content and taste were noted. It is recommended that the fruit of 'K3' melon plants be harvested about 60 days after fruiting to provide consumers with the highest quality for taste and for storage.