• Journal of Bio-Environment Control
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• v.12 no.4
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• pp.195-199
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• 2003

In polyethylene film house treated with surfactants(SF316+FB0800), waterdrops attached on film surface were absorbed to filter paper of 9 cm in diameter and measured 1.21 mL in control, 0.15 mL in 1% and 0.07 mL in 2% on December 10 at 10:00, 2002. However, there was no clear difference between surfactant concentrations 1% and 2%, And the most waterdrop was measured at 10:00 in daytime. As the air temperature was higher in greenhouse, waterdrop was sweled. So, the least waterdrop was measured at 14:00. In greenhouse covered with surfactants concentrated 1% and 2%, transmittances of solar radiation were 9.3% and 12.9% higher than control, respectively. In air temperature and relative humidity, there were no significant difference in all greenhouse. in forenoon, the air temperature and relative surfactant treated film greenhouse tended 1~2$^{\circ}C$ warmer than that of control. However, sil temperatures of surfactant treated film greenhouse tended 3~4$^{\circ}C$ warmer than that of control. During winter, the lettuce growth in surfactant treated film greenhouse was faster than that of control. However, there was no difference between surfactant concentrations of 1% and 2%.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.213-218
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• 2001

In 2000, domestic protected cultivation area was about 52,189 ha including 13,621 ha of heating greenhouses. Recently, heating cost accounts for 25 to 30% of total production cost which has been increased due to the rise of oil price, while the heating cost was about 15% in other advanced countries. To reduce the heating energy cost, the study of minimizing the heating space of greenhouse have been conducted from 1998 to 1999. The system was developed to control the heating space according to crop growth by moving horizontal curtain up and down. Installation of the heating space-control curtain in greenhouse decreased heating capacity to 264 m$^3$compared to 661.5 m$^3$in the traditional curtain, and consumpted fuel was saved about 56% point in semiforcing culture and 28% point in retarding culture of pepper. In addition, uniform distribution of air temperature and relative humidity in greenhouse environment resulted in earlier flowering and higher yields in hot pepper.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.1
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• pp.8-15
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• 2014

In order to evaluating physiochemical properties of soil under minimum tillage and direct seeding cultivation on dry rice paddy, we conducted to analyze the soil physiochemical characteristics in treatment with 2-year minimum tillage and dry direct seeding (2MT), 3-year minimum tillage and dry direct seeding (3MT), and tillage transplanting cultivation (TT). As results of analyzing soil organic matter (OM) contents with 2 cm soil depth of interval from surface to 30 cm, OM contents with surface soil from 0 to 2MT and 3MT were higher than TT, recorded 34.6, 28.1 and $19.8gkg^{-1}$, respectively. But until 20cm in soil depth, it was not so large on the deviation of OM contents among the 3 treatments comparing with 2cm surface. Beneath 20 cm in soil depths, 2- and 3-year, OM contents in TT were distributed to be lower than 2MT and 3MT. The contents of total nitrogen in 2MT and 3MT were higher than the content in TT across the soil profile. Consequently, though minimum tillage and direct seeding farming is obviously the practice to saving of machinery work and labor, other practices such as continuously input OM should be needed to achieve carbon sequestration goal through minimum tillage and direct seeding on dry paddy.

• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.223-229
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• 2017

BACKGROUND: Tillage systems and fertilization play an important role in crop growth and soil improvement. This study was conducted to determine the effects of tillage and fertilization on the microbial biomass C and dehydrogenase activity of soils in a field under cultivation of soybean. METHODS AND RESULTS: An experimental plot, located in the temperate climate zone, was composed of two main sectors that were no-tillage (NT) and conventional tillage (CT), and they were subdivided into four plots, respectively, in accordance with types of fertilizers (non fertilizer, chemical fertilizer, hairy vetch, and liquid pig manure). Microbial biomass C and dehydrogenase activity were evaluated from May to July in 2016. The microbial biomass C and dehydrogenase activity of NT soils were significantly higher than those of CT in all fertilizer treatments, and they were further increased in hairy vetch treatment than the other fertilizer treatments in both NT and CT. The dehydrogenase activity was closely related to microbial biomass C. CONCLUSION: It is concluded that application of green manure combined with no-tillage can provide viable management practices for enhancing microbial properties of soil.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.200-205
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• 2016

This study was conducted in order to investigate the effects that the difference of planting time by a method of cultivation in the non-heated greenhouse and the open field with spring planting had on growth and yield. With regard to the tested variety of Momordica charantia, variety 'Dragon' (Japan Yae 農藝) was selected. And 3 treatments on March 20, April 5 and April 20 for the greenhouse cultivation and 3 treatments on April 20, May 5 and May 20 for the open-field cultivation 1 month later than those for the greenhouse cultivation were planted by the randomized complete block design, and 4 secondary vines were trained. In the results of examining 15-day average atmospheric temperature after planting according to the methods of greenhouse and open-field cultivation and planting time, it was shown that there was a tendency for atmospheric temperature inside the greenhouse to decrease as the planting time was moved up. In particular, the average atmospheric temperature was $16.7^{\circ}C$ when seedling was planted on April 20 in the open-field cultivation, which was approximately equal to $17.0^{\circ}C$ of the average atmospheric temperature when a seedling was planted on March 20 in the greenhouse cultivation. With regard to the date of first harvest by the method of cultivation, it was shown that there was a tendency for the date of first harvest to be earlier in the greenhouse cultivation than in the open-field cultivation, and the date of first harvest was moved up as a seedling was planted earlier for the planting period. The number and weight of harvested fruits per plant showed a tendency which was almost similar to that of total number of harvest days and number of harvests. Thus, the number of fruits was 189 and the weight of fruits was 31,649g in case of the greenhouse cultivation and planting on March 20, which were maximum. In case of planting on the latest planting date : May 20 in the open-field cultivation, the number of fruits was 77 and the weight of fruits was 12,502g, which were at a level of 40% of those of planting on March 20 in the greenhouse cultivation 2 months earlier. The total yield per 10a was 10,228kg in the greenhouse cultivation and was 2.2 times as heavy as 4,607kg in the open-field cultivation with regard to the method of cultivation. For the planting period in the greenhouse cultivation, it was 10,539kg and 10,517kg in planting on March 20 and April 5, which was higher by 9% than 9,629kg in planting on April 20. And in the open-field cultivation, it was 4,785kg in planting on April 20 and 4,872kg in planting on May 5, which was higher by 15~17% than 4,163kg in planting on May 20. Taking the above results into account, it is considered proper to plant Momordica charantia from March 20 to April 5 for the greenhouse cultivation and from April 20 to May 5 or thereabouts when a risk of late frost is gone for the open-field cultivation in southern area.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.292-308
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• 1992

Recently agricultural situations are being placed in unfavourable socio-economic environment as followed by rapid decrease of rural population, poor labor quality and high wages of rural society due to high speedy industrialization of social structure in Korea. In addition to those circumstances, under the UR system to be expected in the early future, free trade of agricultural products will be faced inevitably in Korea. Practically prices of rice as a principle food in this country are expensive about three times compared to those of foreign rice markets, and so how to increase the international competitiveness and food supplies are important problems to be solved rapidly. Accordingly an urgent goal is reduction of agricultural production cost by the improvement of labour productivity as a labour saving and cost down cultivation methods as the direct seeding cultivation in rice. But there are many problems in the direct seeded rice cultivation. The important things to be improved in that cultivation are development of rice varieties with lodging tolerance, effective seedling stand, weed control, irrigation management and fertilizing and so on. Moreover agricultural basis as irrigation facilities, land consolidation and farm machineries must be improved for the stability of rice cultivation in the future.

• Preventive Nutrition and Food Science
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• v.8 no.4
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• pp.336-342
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• 2003

The effects of cultivation methods (cultivation of curled-shaped type, M-1; conventional cultivation, M-2; growing after treatment with a growth regulator, M-3; cultivation by the combination of M-1 and treatment with oak charcoal, M-4) on the quality characteristics of soybean sprouts were studied by the measurement of growth characteristics. This study also investigated the changes in shelf-life stability of the new soybean sprouts (NSB) using M-4, which was cultivated with oak charcoal and treated with antimicrobial Citrus sunki seed extract. Among the soybean sprouts grown for six days at the high temperature and humidity environment (90$\pm$5% RH, 25$\pm$1$^{\circ}C$), M-1 revealed no significant difference in terms of quality, such as the harvest yield, the rot rate and the growth characteristics when compared with M-2. M-3 showed no significant difference in growth characteristics, of hardness, and sensory evaluation scores when compared with the soybean sprouts grown by conventional methods. NSB had a low number of total microorganisms and had a better appearance after five days of storage than did the control group (M-2). These findings demonstrate that chemical-free and clean soybean sprouts can be grown by combining oak charcoal and antimicrobial Citrus sunki seed extract, thereby meeting the consumer demand for safe, chemical free sprouts.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.2
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• pp.1-11
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• 2023

This study analyzed the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes. The groundwater observation data in the Miryang study area were used and classified into greenhouse and field cultivation areas to compare the groundwater impact of water curtain cultivation in the greenhouse complex. We identified the characteristics of the groundwater time series data by the terrain of the study area and selected the optimal model through time series analysis. We analyzed the time series data for each terrain's two representative groundwater observation wells. The Seasonal ARIMA model was chosen as the optimal model for riverside well, and for plain and mountain well, the ARIMA model and Seasonal ARIMA model were selected as the optimal model. A suitable prediction model is not limited to one model due to a change in a groundwater level fluctuation pattern caused by a surrounding environment change but may change over time. Therefore, it is necessary to periodically check and revise the optimal model rather than continuously applying one selected ARIMA model. Groundwater forecasting results through time series analysis can be used for sustainable groundwater resource management.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.6
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• pp.93-103
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• 2023

This study aimed to analyze the impact of water curtain cultivation in the greenhouse complexes on groundwater's electric conductivity and water temperature. The greenhouse complexes are mainly situated along rivers to secure water resources for water curtain cultivation. We classified the groundwater monitoring well into the greenhouse (riverside) and field cultivation areas (plain) to compare the groundwater impact of water curtain cultivation in the greenhouse complex. The groundwater observation network in Miryang, Gyeongsangnam-do, located downstream of the Nakdong River, was selected for the study area. As a result of analyzing the electric conductivity and water temperature, the following differences were found in the observed characteristics by region. 1) The electric conductivity and water temperature of the riverside area, where the permeability is high and close to rivers, showed a constant pattern of annual changes due to the influence of river flow and precipitation. 2) The flat land in general agricultural areas showed general characteristics of bedrock observation in the case of water temperature. Still, it seemed more affected by the surrounding well's water use and water quality. The electric conductivity did not show any particular trend and was influenced by the surrounding environment according to the location of each point.

• Journal of Bio-Environment Control
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• v.16 no.1
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• pp.67-71
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• 2007

This study was conducted to find out the influence of cultivation season for fresh parsley in modified atmosphere storage. As the qualities of fresh parsley grown in different seasons; autumn, winter, summer were compared, the chlorophyll and vitamin C showed the highest content in autumn and winter cultivation, respectively, but the firmness was the highest in summer cultivation treatment. These fresh parsleys grown in different seasons packaged with 0.04mm ceramic film and stored at $0^{\circ}C$. The shelf life of these parsleys were 84 days in winter cultivation treatment, while parsleys cultivated in autumn and summer were able to be stored for 77 days and 56 days, respectively. The fresh weight loss of parsley was much more higher in summer than in both autumn and winter cultivation treatments. The carbon dioxide and ethylene contents in packages in summer were more than twice as high in autumn and winter cultivation treatment. There were not different between autumn and winter cultivation treatment in the two kinds of gas contents. This result should be caused by higher field heat that increased a respiration remarkably during the early storage. The highest field heat produced by summer cultivation resulted in remarkable decreases of firmness, chlorophyll and vitamin C during MA storage. As the results, the fresh parsley showed highest storability in winter cultivation treatment. The field heat of fresh parsley should be eliminated just after harvest for a long term storage.