• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.50-56
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• 2002

This experiment was carried out to obtain some information about overwintering, physiological and ecological characteristics of apple snails. Another purpose of this experiment was to characterize an appetite for rice plants by apple snails and to elucidate their choice of fresh green ones (vegetables, some other crops, weeds in rice fields). The freshwater snails were found with higher population at sites abundant organic compounds such as plant debris and at regions with high temperature. They also prefer calcium-rich water. This is a naturally occurring process. Apple snails were exceptionally veil-adapted to the south regions of Korea, especially Janghang, Jangseong and Haenam, even if the temperature of winter season is cold below 0$^{\circ}C$. Apple snails were not very selective in their food choice and eat almost everything available in their environment. A snail have something called a radula in its mouth for grinding up its food. A apple snail also chews on fruits and young succulent plant barks. In case of reproduction. apple snails deposit about 157$\sim$784 (average of 321 eggs) milky white to pale orange colored eggs above the waterline. In approximately every 22.4 seconds a new egg appears. The total time needed to deposit a egg mass varies from 58 minutes$\sim$4 hours 13 minutes. Apple snails reproduct actively from May to June and from September to October. An appetite of apple snails for rice plants was the different depending on their size and glowing stage for rice plants. Apple snails had a great appetite of rice plants as well as dropwort, tomato, cabbage, radish, aquatic plants etc. They preferred to eat young rice plants and drastically quit eating rice plants of over 40 cm in height. Thus considering the food preference of apple snail for various plants including rice, they were thought to be a potentially strong predator in fields, especially, at regions with warmer winter.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.237-243
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• 2021

The objective of this study was to evaluate the effect of stem number on plant growth, fruit quality, and yield of sweet peppers grown in greenhouses under supplemental lighting in winter. The seedlings were transplanted at 3.2 plants·m^-2 on October 26, 2020, and started supplemental lighting with 32 high pressure sodium lamps for 16-hour photoperiod from December 1, 2020 to May 25, 2021. Stems were differently trained with 2 and 3 numbers after branching nodes were developed. In the final harvest, the plant height was significantly shorter in the 3 stem-plants than in the 2 stem-plants. The number of nodes per stem and the leaves per plant were increased in the 3 stem-plants than in the 2 stem-plants, while the leaf area was less affected. There were no significant differences in the dry mass of leaves, stems, and immature fruits between the 2 and 3 stem-plants. The fruit fresh weight and fruit dry weight in the 3 stem-plants were decreased by 17% and 12% at 156 days after transplanting (DAT), and by 17% and 15% at 198 DAT compared to those in the 2 stem-plants, respectively. The marketable fruit rates were 93.6% and 95.4% in the 2 and 3 stem-plants, respectively. The total fruit yield in the 3 stem-plants was increased by 30.2% as compared to that in the 2 stem-plants. We concluded that the 3-stem-training cultivation positively affected the total fruit yield by sustaining adaptive vegetative growth of the plants. This result will help producers make useful decisions for increasing productivity of sweet peppers in greenhouses.

• Journal of Korean Society of Neurocognitive Rehabilitation
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• v.10 no.2
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• pp.53-62
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• 2018

The purpose of this study was to propose an alternative for the eating habits of modern people and coping with the diseases. The purpose of this study was to apply the principles of eating habits of people living in Roma Linda to modern dietary life and to help healthy life and prevent disease. The period of this study was from May 1, 2016 to February 28, 2018. Literature search was conducted using Pubmed and Korean academic web sites. Based on the recognition of wrong eating habits, we classify and classify diseases according to eating habits. A total of more than 100 papers were selected and 60 papers and a database were prepared. People living in Roma Linda have eight health principles. The Roma Linda practiced balanced nutritional intake, sufficient exercise, adequate water intake, sunlight, temperance (abstinence from alcohol etc.), fresh air, adequate rest, and trust in eating habits. People living in Roma Linda have a high intake of vegetables, fruits and nuts. People living in Roma Linda are educated about nutrition, and among them, there is a low prevalence of coronary heart disease and cancer, because they mostly do not smoke or drink alcohol. Unhealthy eating habits and dietary behavior are associated with many diseases. Many chronic, degenerative diseases are due to bad eating habits and stress. If you take good food habits of people living in the Roma Linda area and practice it steadily, it will have a great effect on disease prevention.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.468-475
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• 2022

This study was conducted to find out the efficiency of heating initiative temperature and carbon dioxide fertilization in summer squash (Cucurbita moschata D.). The heating start temperature experiment was performed at 9℃, 12℃, and 15℃ using an electric heater and operated when the temperature was lower than the target temperature. The CO₂ fertilization concentration experiment was performed from 7 to 12 with the control, 500 µmol·mol^-1, and 800 µmol·mol^-1 using liquefied carbon dioxide. Investigation items were plant height, stem diameter, number of leaves, leaf area, fresh weight, dry weight, also economic analysis was conducted by surveying only fruits exceeding 100 g. Photosynthesis was measured for the upper leaf position to calculate the saturation point according to the control. The photo saturation point was 587 µmol·m^-2·s^-1, and the CO₂ saturation point was 702 µmol·mol^-1. A_max values by carbon dioxide were 13.4, 17.8, 17.2, 19.6, and 17.5 µmolCO₂·m^-2·s^-1 in the order of 9℃, 12℃, 15℃, 500 µmol·mol^-1, and 800 µmol·mol^-1. In the temperature experiment, 9℃ in growth did not grow normally and no fruiting was performed. 12℃ and 15℃ were higher than 9℃, but there was no significant difference in growth and production. The CO₂ fertilization experiment showed no significant difference between the treatment in growth, but the productivity of 800 µmol·mol^-1 was the best. Comprehensively, the heating initiative temperature of 15℃ was good for crop growth and production, but there is no significant difference from 12℃, so it is good to set the heating start temperature to 12℃ economically, and maintaining of 800 µmol·mol^-1 is effective in increasing production.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.223-229
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• 2022

This study was conducted to investigate the effect of packaging methods and sterilization treatment on storability and microbial control in paprika fruits. When treated with chlorine dioxide gas for 3, 6, and 12 hours and cold plasma gas for 1, 3, and 6 hours, and then packed in a carton box and stored in a 8 ± 1℃ chamber for 7 days, chlorine dioxide treated 12 hours and plasma treated 6 hours was prevented the development of E·coli and YM(yeast and mold). Accordingly, the control was treated with chlorine dioxide for 12 hours and plasma for 6 hours, packed using a carton box and 40,000 cc·m^-2·day^-1·atm^-1 OTR film (MAP), and stored in a 8 ± 1℃ chamber for 20 days. Fresh weight loss rate during storage was less than 1% in the MAP treatments, and the visual quality of the MAP treatments was above the marketability limit until the end of storage. There was no difference in the contents of oxygen, carbon dioxide, and ethylene in the film. In the case of firmness, the chlorine dioxide treatments was low, and the Hunter a^* value, which showed chromaticity, was highest in the Plasma 6h MAP treatment. Off-odor was investigated in the MAP treatments, but it was very low. The rate of mold growth on the fruit stalk of paprika was the fastest and highest in the chlorine dioxide treated box packaging treatments, and the lowest in the chlorine dioxide treated MAP treatments at the end of storage. The aerobic count in the pulp on the storage end date was the lowest in the plasma treated box packaging treatments, the lowest number of E·coli in the chlorine dioxide treated MAP treatments, and the lowest yeast & mold in the chlorine dioxide treated box packaging treatments. As a result, for the inhibition of microorganisms during paprika storage, it is considered appropriate to treat plasma for 6 hours before storage regardless of the packaging method.

• Journal of Bio-Environment Control
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• v.33 no.1
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• pp.55-62
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• 2024

This study aimed to compare the nutrient uptake rate, growth and yield of strawberry grown under the aquaponic and hydroponic systems in a plant factory. For aquaculture, 12 of fish (Cyprinus carpio cv. Koi) were raised in an aquaponics tank (W 0.7 m × L 1.5 m × H 0.45 m, 472.5 L) filled with 367.5L of water at a density of 5.44 kg·m^-3. The 30 seedlings of strawberry were planted in ports filled with perlite substrate and then were placed on the bed (W 0.7 m × L 1.5 m × H 0.22 m) at the top of the aquaponics system, and the 30 seedlings were planted in net-pots and then placed on the holes of acrylic plates (140 cm × 60 cm, Ø80 mm) on the bed (W 0.7 m × L 1.5 m × H 0.22 m) at the deep flow technique (DFT)- hydroponics. The pH and EC of the aquaponic solution was ranged from 4.3 to 6.9 and 0.32 to 1.14 dS·m^-1, respectively, while those of hydroponics were ranged from 5.1 to 7.5 and 1.0-1.8 dS·m^-1, respectively. The NO₃-N and NH₄-N concentration of the aquaponic solution were higher about 3.6 and 2.2 me·L^-1 than those of the standard hydroponic solution for strawberry cultivation. The P, Ca, Mg, and S ions in the aquaponic solution were also higher about 0.76, 3.1, 0.8, and 0.9 me·L^-1 than those of standard hydroponic solution, respectively, while the K and Fe were lower about 0.8 me·L^-1 and 0.5 mg·L^-1, respectively. The mineral contents of the strawberry leaves grown on aquaponics did not differ from that of hydroponics, and K content in the leaves were in an appropriate range. Uptake rates of T-N and P between the 58 and 98 days after transplant (DAT) were 1.5 and 1.9-fold higher in the aquaponics than those of hydroponics, respectively with no significant difference in the uptake rate of K. The crown diameter, plant height, and leaf length and width in the 98 DAT were significantly higher in aquaponics. The number of fruits per plant was significantly higher in aquaponics than those in hydroponics, and the fresh and dry weights of fruit and length and width of fruit were significantly higher in hydroponics. The results suggest that plants in aquaponics continuously utilize fertilizer components of solid particles from fish and feed wastes.