• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.328-334
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• 2019

Shading paint (water-soluble) is one of the temperature control agents inside of a greenhouse in summer. Plastic film rain shelter is a unique system in Korean, prevents disease development vineyards, but it causes the heat inside a shelter in summer. Shading paint treatment with different shading rates (15, 25, and 35%) outside of plastic rain shelter avoided excessive heat inside. Shading paint influenced sunlight under plastic rain shelter in a different manner at each treatment. 35% of shading paint treatment reduced 45% of PPFD (Photosynthesis Photon Flux Density) than non-treatment control. Shading paint had the significance of efficiency to reduce the temperature under plastic rain shelter. 35% of shading paint treatment reduced $2^{\circ}C$ of bunch temperature than non-treatment control. However, shading paint treatment had not to control lower than ambient temperature. 35% of shading paint treatment is available to prevent excessive heat damage and poor fruit quality under plastic film rain shelter in summer in Korean vineyards.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.355-362
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• 2016

This study was carried out to investigate the effects of rain-shelter types on growth, and fruit quality of red pepper (Capsicum annuum, 'Kemmaru') cultured in paddy. Applied rain-shelter types were outfield (control), simple rain-shelter plastic house with 2 rows (2R), simple rain-shelter plastic house with 4 rows (4R), and perfect plastic house (House). The plant height was the highest in Houses treatment. There was no difference in leaf length and width among the rain-shelter treatments. The fresh and dry weight of red pepper was high in order of House > 4R > 2R > Control. The ASTA value is irregular tendency among the treatments. Hunter's color value 'a' and 'b' was not different from among the treatments. Phytophthora blight, powdery mildew, bacterial spot were not occurred in all of treatments, and Anthracnose was only occurred in control. Mite, Microcephalothrips abdominalis, and Bemisia tabaci were not occurred in all of treatments, and aphid, Helicoverpa assulta, and virus were occurred all of treatments as same degree. Our results will provide rain-shelter cultivation of red pepper can be increase dry yield and decrease disease and insects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.187-190
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• 2005

This study was conducted to investigate the plant growth and seed yield between rain-shelter plastic house and out-door cultivation, and analysed the effect of harvesting time on seed quality. In rain-shelter plastic house cultivation, emergence date was 3 days and flowering date was 8 days earlier than out-door cultivation. Seed yield of rain-shelter plastic house cultivation was increased $25\%$ compared to out-door cultivation and it's more beneficial than out door cultivation. The crude fat content was higher and seed was whiter and better quality in rain-shelter plastic house cultivation than out-door cultivation. In out-door cultivation, the crude fat content was steadily increased until 40 days after full bloom, but the seed color was getting dark which was harvested at 30 days after full bloom and the color was turn to the dark brown when the seed was harvested at 40 days after full bloom. Harvesting of safflower seed's quality is best between 20 days and 30 days after full bloom.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.113-118
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• 2015

The objective of this experiment was to evaluate the effects of application wide plastic shelter (WPS) in the 'Campbell Early' grape. WPS was developed 30cm wider than standard plastic shelter (SPS; 210cm). Under the plastic shelter, the average daily temperature was $2{\sim}3^{\circ}C$ higher than ambient temperature, but WPS treatment was $0.5{\sim}1^{\circ}C$ higher than SPS treatment. However, relative humidity 15~20% lower than ambient and shown different result between two treatments annually. The occurrence of brown leaf spot disease caused by Pseudocecospora vitis on the vineyard decreased 55.6% (2012) and 17.2% (2013) under WPS than SPS. Grape bunches collected two harvest seasons (2012, 2013), were analyzed fruit quality (total soluble solid; TSS, titratable acidity; TA, berry weight, berry size). In 2012, grapes had no differences in the quality of two treatments, but in 2013, significantly increase $0.4^{\circ}Bx$ of TSS and decrease 0.8% of TA on the WPS than SPS. It suggests that the application WPS reduced the incidence of brown leaf spot disease annually, and then affect to the fruit quality.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.293-302
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• 2014

This study was carried out to develop rain shelter which can make an appropriate size and environment for Chinese cabbage rainproof cultivation. Fifty three farms with chinese cabbage rainproof cultivation system have been investigated to set up width and height of rain shelter. Mostly the width of 6m was desired for rain shelter and the height of 1.6m for their eaves, so these values were chosen as the dimensions for rain shelter. After an analysis of their structural safety and installation costs by the specifications of the rafter pipe, Ø$25.4{\times}1.5t$ and 90cm have been set as the size of rafter that such size costs the least. This size is stable with $27m{\cdot}s^{-1}$ of wind velocity and 17cm of snow depth. Therefore it is difficult to apply this dimension to area with higher climate load. In order to sort out such problem, the rain shelter has been designed to avoid damage on frame by opening plastic film to the ridge. Once greenhouse band is loosen by turning the manual switch at the both sides of rain shelter and open button of controller is pushed then switch motor rises up along the guide pipe and plastic film is opened to the ridge. Chinese cabbage can be damaged by insects if rain shelter is opened completely as revealed a field. To prevent this, farmers can install an insect-proof net. Further, the greenhouse can be damaged by typhoon while growing Chinese cabbage therefore the effect of an insect-proof net on structural safety has been analyzed. And then structural safety has been analyzed through using flow-structure interaction method at the wind condition of $40m{\cdot}s^{-1}$. And it assumed that wind applied perpendicular to side of the rain shelter which was covered by insect-proof net. The results indicated that plastic film was directly affected by wind therefore high pressure occurred on the surface. But wind load on insect-proof net was smaller than on plastic film and pressure distribution was also uniform. The results of structural analysis by applying pressure data extracted from flow analysis indicated that the maximum stress occurred at the end of pipe which is the ground part and the value has been 54.6MPa. The allowable stress of pipe in the standard of structural safety must be 215 MPa or more therefore structural safety of this rain shelter is satisfied.

• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.497-505
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• 2023

This study evaluated the impact of rain shelters made of plastic film on spring frost damage and fruit quality in Asian pears ('Niitaka') over two years. In 2021, during the coldest spring days (between 0:00 am and 7:00 am), temperatures dropped to -1.20 - 0.43℃ at 120 cm and -1.33 - 0.57℃ at 200 cm above ground level in the control. Conversely, the rain shelter treatment maintained higher temperatures, -0.40 - 0.87℃ at 120 cm and -0.43 - 0.77℃ at 200 cm. Flower damage was significantly lower in the rain-sheltered group, with incidences of 1.3 and 6.9% at 120 and 200 cm, respectively, compared with 18.1 and 22.6% in the control group. Visual observations verified the prevention of frost adhesion on flower organs in the sheltered group, compared with noticeable pistil death and petal browning in the control group. In 2022, when temperatures remained above 0℃, fruitlet stalk length was 5 - 6 mm longer in the sheltered group. The cumulative impact of rain shelters was evident in the improved fruit quality over the two years. This study suggests resilient cultivation strategies in the face of climate change to reduce frost damage, increase productivity, improve fruit quality, and potentially increase incomes of the farmers.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.269-274
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• 1999

This experiment was carried out to investigate the effect of rain shelter cultivation on the its quality of safflower. The development and growth of safflower, especially the number of secondary branches per plant was increased by rain shelter. Under the rain shelter started earlier, the seed yield was increased by 95% compared with that of non-shelter condition. The number of plants in a unit area the number of flower buds and seeds per plant and seed weight were increased in rain shelter condition. As those plants were cultivated under the rain shelter, lightness(L) of their seeds was increased but redness (a) and yellowness (b) were decreased.

• Journal of Aquaculture
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• v.22 no.1
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• pp.118-121
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• 2009

This experiment was conducted to evaluate the effects of different substrates in rearing tank on growth and body composition of juvenile sea cucumber Apostichophus japonicus. Sea cucumber (average weight 3.6) were randomly distributed at a density of 10 juvenile per tank into nine tanks providing three different substrates including free-substrates, sand and wave-shaped plastic sheet as (shelter). Juveniles were fed with a commercial feed once in every 2 days for 8 weeks. At the end of the experiment, survival of sea cucumber was not affected by the presence of substrates (P>0.05). Weight gain and specific growth rate of sea cucumber reared in the tanks with sand were significantly higher than those of sea cucumber reared in the tanks with shelter and without substrate (P<0.05). Crude protein and crude lipid of whole body in sea cucumber reared in free-substrate tanks were significantly higher than those of juvenile reared in the tanks with other substrates (P<0.05). Higher ash content was obtained in sea cucumber reared in the tanks with sand compared to that of juvenile reared in the tanks with other substrates (P<0.05). The results of this study suggest that growth and proximate composition of whole body of sea cucumber was significantly affected by substrates. Among materials tested, sand may be a proper substrate for sea cucumber culture.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.80-87
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• 2022

Most of the disaster relief items provided to sufferers and temporary evacuees that are supposed to be victims in Korea are not suitable for the shelter environment of temporary housing facilities, and are not satisfactory because they do not have the functions, proper size and types. The purpose of this study is to analyze the user needs of emergency rescue relief items by presenting problems about the use environment and to develop the variable air mattresses which are based on disaster prevention design. In order to secure objectivity such as usability, convenience, and durability, research data are limited. However, the difficulty of mass spreading of conventional fiber mat and the functional disadvantages of foam plastic mat are solved by adopting variable air mattresses. The variable air mattresses are expected to help rehabilitate people by helping victims of physical tiredness, illness worsening, poor sleep, and life instability that can happen during long-term shelter life.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.4
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• pp.243-247
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• 2007

We investigated the reproductive behavior of Octopus minor, order Octopoda, class Cephalopoda under laboratory conditions. Each mature female octopus was kept in an aquarium with a plastic tube for shelter, and one mature male was introduced for the purpose of copulation. Before spawning, the female coated the roof of the shelter with a light-green material, upon which it then fixed its eggs one by one. This spawning behavior lasted 1 to 3 days. Fertilized females spawned 54 eggs on average, ranging from 21 to 112 eggs at 72 to 98 days after copulation. The attached eggs were 18.1-19.0 mm in length, 5.0-6.1 mm in width, and 0.30-0.38 g in weight. The mother octopods did not feed; they attended to the eggs by using their arms to rub the egg surfaces and used their funnel to blow sediments off of the eggs. At water temperatures of $20.9-21.5^{\circ}C$, the fertilized eggs hatched within 73 to 90 days after being spawned. The effective cumulative water temperature was $1,569-1,892^{\circ}C$. At the end of incubation, the body weight of the mother octopods was reduced to approximately 56% of the initial weight, and most mother octopods died soon after the young hatched.