• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.162-166
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• 2006

The objectives of this study were to determine the effect of cultivation time on the incidence of brown fruit stem (BFS) in glasshouse sweet pepper (cv. Special) and to investigate environmental causes of this disorder. The plants transplanted on 31 August (T1) showed more incidence of BFS than those on 24 November (T2) (6.1% vs.2.9%; P<0.01). The BFS symptom began to appear after completion of fruit enlargement, more often around fruit coloring period. Comparing the environmental factors between T1 and T2, with their data collected for 3 weeks around fruit coloring period, the factor that was most likely responsible for BFS incidence was found to be the night-time humidity deficit (HD) ($1.9g{\cdot}m^{-3}\;vs\;2.9g{\cdot}m^{-3}HD$). These results were reconfirmed as T1 was compared to the plants (T3) that were transplanted at a similar time of the following year to T1, but designed to reduce BSF by increasing air HD via heating at night. That is,T3 had much higher night-time HD than T1 ($5.9g{\cdot}m^{-3}\;vs\;1.9g{\cdot}m^{-3}HD$), and showed no incidence of BFS. These results indicated that, to prevent BFS incidence in the winter-harvesting sweet pepper plants, air humidity at night should be controlled low, especially for the fruit coloring period after fruit enlargement period is completed.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.121-126
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• 2003

Tomato (Lycopersicon esculentum M. cv. ‘Momotarou’) and hot pepper seedlings (Capsicum annuum L. cv. 'Nockkwang')were grown under the 24h photopeliod (12 hrs light period: 12 hrs dark period) and 6 h photoperiod (3 hrs light period: 3hrs dark period). As a result of this experiment, the following details were observed. Plant height, leaf area, total dry weight, and leaf chlorophyll content decreased in case of tomato seedlings when they were given 6 h photoperiod. But the same effect was not observed in case of hot pepper seedlings. The photoperiod, however, did not produce any significant effect on the uptake of N, P, K, Mg and Ca ions in their nutrient solutions with the exception of their Fe. On thc 10th day of treatment, leaf chlorosis started to become visible in tomato seedlings and at the same time the uptake of Fe went down when the 6h photoperiod was applied to both tomato and hot pepper scedlings. In addition to this phenomenon, the sucrose content in leaf increased in case of tomato plants which were treated with 6 h photoperiod; on the other hand, their glucose content was observed to have decreased.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.219-230
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• 2020

This study was conducted to determine the optimum medium and humidification period for the strawberry (Fragaria × ananassa Duch. cv. Maehyang) cutting seedling production. The cuttings were planted in coir (CO), rockwool (RW), phenolic foam (PF), and organic foam medium (OFM) with fogging treatment in 0, 3, 6, 9, or 12 days on February, 2019. And, as the field verification examination research, cuttings were planted in CO, RW, PF, and OFM, with misting treatment in 0, 6, 9, 12, or 15 days on June, 2019. In fogging treatments, rooting and survival rates of seedlings tended to increase with longer fogging periods, and rooting and survival rates were showed significantly higher in CO medium with more than 9 days of fogging periods. In misting treatments, rooting rate was significantly higher in CO and RW medium with more than 9 days of misting periods, and survival rate was significantly higher with more than 12 days of misting periods. There was no significantly difference by growth medium and humidification period in shoot and root growth. Therefore, when considering the rooting and survival rate the CO medium with 9 days of humidification period could be beneficial for the production of the 'Maehyang' strawberry cutting seedlings.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.981-988
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• 2008

This study was conducted to develop functional black soy sauce with (S2) and without (S3) an outer skin and then compare these products to a control soy sauce (S1). In addition, the effects of different fermentation periods on the pH, buffering power, titratable acidity, total acidity, salt content, and browning and Lab value were evaluated. Furthermore, the antioxidative activities of the black soy sauce were compared to those of the control soy sauce based on the total phenolic compounds and free radical scavenging activity, including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenging activity and the thiobarbituric acid value (TBA value). The pH and buffering power of S2 were lower than of S1 and S3, while the titratable acidity and total acidity were higher. The salt content of all samples decreased after 60 days of fermentation, after which it increased slightly for up to 180 days. Additionally, the browning intensity of all samples increased as the fermentation periods increased, with the browning intensity at 420 nm of S1 being the highest followed by S3 and S2. After 150 days of fermentation, the L value of S1 was higher than that of S2 and S3, but the while a value of S2 was higher than those of S1 and S3 and was increased as the fermentation periods. Moreover, the b value of S1 was the highest at the end of the fermentation period, followed by the b values of S3 and S2. The amount of total phenolics in S1 was greatest, followed by S2 and S1. Conversely, the DPPH radical scavenging activity of S2 was the highest, followed by S3 and S1. Finally, the TBA value increased rapidly from day 30 to day 180 of the fermentation period, and the TBA value of S2 was lower than those of S1 and S3.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.115-119
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• 2000

Oak mushroom(Lentinus edoes(Berk) Sing) is one of the most important edible mushrooms, and its production has been rapidly increased due to nutritional and medicinal effects. In this study, climatic factors during the growing period of high-quality oak mushroom were analyzed and environmental factors affecting the quality of oak mushroom were discussed. Three places(Changheung, Puyo and Wonj) as mass producing areas of high-quality oak mushrooms and the 15 days of the growing period in 1997-1998 were selected. Major climatic factors for analysis were average air temperature, average relative humidity, ranges of daily air temperature, relative humidity, and wind speed. During the period, th daily average air temperature was $7~20^{\circ}C$ with the diurnal air temperature($7~20^{\circ}C$) and nocturnal air temperature($0~-2^{\circ}C$). The relative humidity ranged between 50 and 70% with the range of daily relative humidity(40~60%). Wind velocity was 1~4m.$s^{-1}$, From the results, it is concluded that the growing environmental conditions for high-quality oak mushroom differed from the optimum conditions for the high productivity of oak mushroom; environmental conditions such as wide ranges of air temperature and relative humidity, low humidity and wind speed might affect the emergence of high-quality oak mushroom.

• Korean Journal of Applied Biomechanics
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• v.20 no.4
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• pp.395-406
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• 2010

The purpose of this study was to analyze the changes in kinematic and kinetic parameters of lower extremity joint according to rehabilitation period. Fourteen collegiate male athletes(age: $22.1{\pm}1.35$ years, height: $182.46{\pm}9.45cm$, weight: $88.63{\pm}9.25kg$) and fourteen collegiate athletes on functional ankle instability(age: $21.5{\pm}1.35$ years, height: $184.45{\pm}9.42cm$, weight: $92.85{\pm}10.85kg$) with the right leg as dominant were chosen. The subjects performed drop landing. The date were collected by using VICON with 8 camera to analyze kinematic variables and force platform to analyze kinetic variables. There are two approaches of this study, one is to compare between groups, the other is to find changes of lower extremity joint after rehabilitation. In comparison to the control group, FAI group showed more increased PF & Inversion at IC and decreased full ROM when drop landing. Regarding the peak force and loading rate, it resulted in higher PVGRF and loading. FAI group used more increased knee and hip ROM because of decreased ankle ROM to absorb the shock. And it used sagittal movement to stabilize. In terms of rehabilitation period, FAI group showed that landing patterns were changed and it increased total ankle excursion and used all lower extremity joint close to normal ankle. Regarding the peak force and loading rate, FAI group decreased PVGRF and loading rate. and also showed shock absorption using increased ankle movement. And COP variable showed that proprioception training increased stability during 8 weeks. The results of this study suggest that 8 weeks rehabilitation period is worthwhile to be considered as a way to improve neuromuscular control and to prevent sports injuries.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.13-18
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• 1977

In order to improve the storage ability of Spur Red Delicious apple, calcium ingredients were applied to the apple tree during the growing period, and then the effects of calcium on appearances and respiratory activity of harvest apples were investigated during the storage period. The results of this work were summarized as follows: 1. The freshness of apples treated by calcium compounds reached $73{\sim}78%$, but that of control group was 68% by March of next year. 2. The respiratory rate of the apples that had been applied the high concentration of ammonium sulfate in field during the growing period, was accelerated rather than control group, and that of calcium treatment groups was continuously inhibited during the storage period. 3. The direct foliar application of calcium compounds in the field was more effective than dipping apples in calcium chloride solution for better quality and improving storage ability after harvest. 4. The freshness and hardness relatively not much decreased in calcium treatment groups even after 5 month storage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.793-800
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• 2018

It is necessary to determine an optimal design frequency for establishing stable flood control against frequent flood disasters. Depending on the importance of river and regional characteristics, design return periods are suggested from at least 50 years up to 200 years for river design. However, due to the wide range of applications, it is not desirable to reflect the geographical and flood control characteristics of river. In this study, Bayes theory was applied to seven evaluation factors to determine the optimal design return period of rivers in Chungcheongnam-do; urbanization flooded area, watershed area, basin coefficient, slope, water system and stream order, range of backwater effect, abnormal rainfall occurrence frequency. The potential flood damage (PFD) capacity was estimated considering climate change and the appropriate design return period was determined by analyzing the capacity of each district. We compared the design return periods of 382 rivers in Chungcheongnam-do with the existing design return periods. The number of rivers that were upgraded from the existing return period were 65, which have relatively large flooding areas and have large PFDs. Whereas, the number of rivers that were downgraded were 169.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.188-193
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• 2022

The Korean mint (Agastache rugosa Kuntze) is used as a leaf vegetable. Therefore, it is important to improve the quality and quantity of leaves by maintaining vegetative growth. When the development of a plant is switched from vegetative to reproductive growth, leaf development may be lowered, leading to a decrease in marketability. Therefore, this study was conducted to investigate the effect of the photoperiod on the flowering characteristics and inflorescence development of the Korean mint to select an appropriate photoperiod for leaf production. The seeds were sown in 105-cell trays on 29 November 2021, and planted in each pot on 27 December 2021, when four main leaves appeared. After planting, the light/dark period was adjusted to 10/14hrs, 12/12hrs, 14/10hrs, 16/8hrs. After 19 days of planting, the first flowering occurred in 10/14hrs, which had a short photoperiod, and the 12/12hrs had 20 days for flowering, and other treatments had 21 days. In addition, it was confirmed that the Korean mint has the characteristics of facultative quantitative short-day plant, through the increase in the development of inflorescences as the light period is shorter than the dark period. As for the growth of Korean mint, the longer the photoperiod, the higher values were shown with leaf length, number of leaves, fresh weight, dry weight, and leaf area of the shoot. Therefore, it is considered that 14 h or more light period is suitable for increasing the productivity of Korean mint as a leafy vegetable.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.208-217
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• 2023

Accurate estimation of dormancy breaking and first bloom dates is crucial for effective fire blight control by disease model such as Maryblyt in apple orchards. The duration from dormancy breaking to first bloom in apple trees was influenced by daily minimum temperatures during the dormant period. The purpose of this study is to investigate the relationship between minimum temperatures during this period and the time taken for flowering to commence. Webcam data from eight apple orchards, equipped by the National Institute of Horticultural and Herbal Science, were observed from 2019 to 2023 to determine the dates of starting bloom (B1). Additionally, the dormancy breaking dates for these eight sites were estimated using an apple chill day model, with a value of -100.5 DD, based on collected weather data. Two regressions were performed to analyze the relationships: the first regression between the number of days under 0℃ (X₁) and the time from calculated dormancy breaking to observed first bloom (Y), resulting in Y = 0.87 × X₁ + 40.76 with R² = 0.84. The second regression examined the starting date of breaking dormancy (X₂) and the duration from dormancy breaking to observed first bloom (Y), resulting in Y = -1.07 × X₂ + 143.62 with R² = 0.92. These findings suggest that apple anti-chill days are significantly affected by minimum temperatures during the period from dormancy breaking to flowering, indicating their importance in fire blight control measures.