• Journal of Biosystems Engineering
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• v.40 no.3
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• pp.193-200
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• 2015

Purpose: The purpose of this study was to investigate the energy saving effects and characteristics of plant growth in a greenhouse with an aluminum multi-layer curtain compared to a greenhouse with non-woven fabric. Method: The dimensions of both greenhouses $43m{\times}3.6m{\times}8m(L{\times}H{\times}W)$, and both used hot air heater systems for maintaining a constant temperature $15^{\circ}C$. Heating characteristics such as solar intensity, inside and ambient temperatures, and fuel consumption were measured and analyzed. Results: The changes of average temperature of both greenhouses during a 15-days (December 06 - 20) showed approximately $26^{\circ}C$ at around 2 pm when the ambient temperature was highest. The greenhouses were set by the heater to keep a temperature of $15^{\circ}C$ from 4 pm to 8 am the following day. The average heat loss (for 15 days) from the greenhouse with an aluminum multi-layer curtain was $161.2-268.4kJ/m^2{\cdot}h$ during the daytime and $152.3-198.1kJ/m^2{\cdot}h$ during the nighttime. The average heat loss (for 15 days) from the greenhouse with non-woven fabric was $155.7-258.9kJ/m^2{\cdot}h$ during the daytime and $144.9-207.0kJ/m^2{\cdot}h$ during the nighttime. The total heat loss (for one day) from the non-woven fabric system was $7,960kJ/m^2$($2,876kJ/m^2$ during the daytime, $5,084kJ/m^2$ during the nighttime). The heat supply over 36 days for the non-woven fabric system was higher than the aluminum multi-layer curtain system by $616.3-65,079.4kJ/m^2$. Conclusions: These results suggest that a greenhouse with an aluminum multi-layer curtain could save energy usage by 35% over a greenhouse with non-woven fabric.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.213-216
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• 2011

Gray mold symptoms were frequently observed on green twigs, blossoms, leaves, and fruits of blueberry trees grown in greenhouses in Cheongyang, Dangjin, Daejeon, and Jeju during disease survey in eight locations of Korea from 2007 to 2010. The disease symptoms were not observed in the fields of the other locations investigated. The disease incidence ranged 1~30% in the greenhouses investigated. A total of 27 single spore isolates of Botrytis species were obtained from the gray mold symptoms, and all the isolates were identified as Botrytis cinerea based on their morphological and cultural characteristics. Four isolates of the fungus were tested for pathogenicity to leaves of four varieties of blueberry trees by artificial inoculation with conidial suspensions. All the tested isolates caused gray mold symptoms on the leaves, which were similar to those observed in the greenhouses. This is the first report that B. cinerea causes gray mold of blueberry trees grown in greenhouses in Korea.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.6
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• pp.9-20
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• 2015

The demand of renewable energy is expected to grow in the long run in spite of current stable lower oil prices. Energy consumption for heating in horticulture greenhouse is large and affects the profits of the farms. This study analyzed the availability of biomass in rural area and proposed the strategies for utilizing the biomass for greenhouse heating. Data reveal the annual average fuel consumption in greenhouses is about 78 TOE/ha. Considering biomass resource in rural areas, agricultural residues are not sufficient to meet the biomass demand from greenhouses. Therefore it is recommended to secure further biomass including wild herbaceous biomass and woody biomass from forest. Based on the conditions of biomass gasification equipment investment and fuel prices, maximum allowable price of biomass turned out about 100,000 KRW/t to be competitive to kerosine. Biomass supply chain should be established for facilitating biomass trading between biomass consumers and biomass producers such as farmers who provide crop residues. An online trading system is an example of the system where consumers who utilize biomass make payments to suppliers and get the information about the biomass. Intermediate collection storages are required to store biomass from distributed sources. Operation of biomass heating systems in demonstration greenhouses is necessary to get information to refine and further develop commercial biomass heating systems. Relatively large greenhouses are desirable to have biomass heating systems for economic viability. The location of the greenhouse farms should be selected within the area where enough biomass resources are available for feeding the biomass facility.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.247-254
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• 2021

An outbreak of the onion thrips, Thrips tabaci, was observed in welsh onion cultured in greenhouse during winter season (Jan ~ Feb). The thrips was identified using DNA barcode. Weekly occurrence was around 240 ~ 700 adults per trap. Trap color gave significant influence on the capture efficiency with a preference on yellow compared to blue sticky trap. Subsequently, most (> 90%) onions exhibited a damage symptom induced by the thrips. This outbreak was observed only in a specific area but not in nearby greenhouses. This discontinuous occurrence pattern was further investigated by analyzing flight behavior through in- and out- door tests. About 1.5 mm-body length adults could jump up to about 5 cm and fly up to 2 m in altitude, which was the top of the greenhouse. This suggested their migrating potential to nearby (< 2 m) greenhouses. However, few were detected in the neighboring places probably due to physical hindrance with low temperatures between greenhouses. This is reasoned why the onion thrips forms a patch distribution among greenhouses during winter season.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.39-45
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• 2021

To establish the environmentally friendly biological control of two-spotted spider mites (TSSM), Tetranychus urticae, in exported strawberry greenhouses, the TSSM density reduction efficiency of chemical and biological control measures was compared in commercial, exported strawberry greenhouses. In the biological control greenhouse, only Phytoseiulus persimilis, a natural enemy of TSSM, was released, and the chemical control greenhouse was only sprayed with commercial chemical pesticides. The density of each developmental stage of TSSM was higher in the chemical control greenhouse than in the biological control greenhouse. The management costs were lower for the biological control greenhouse than the chemical control greenhouse. These results suggest that it is possible to effectively control TSSM using P. pesrsimilis in exported strawberry greenhouses.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.4
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• pp.210-219
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• 2023

The decline in the rural populace and an aging workforce have led to fatalities due to worsening environments and hazards within vinyl greenhouses. Therefore, it is necessary to automate crop cultivation and disease detection system in greenhouses to prevent labor loss. In this paper, an object detection-based model is used to detect diseased crop in greenhouses. In addition, the system proposed configures the environment of the artificial intelligence model in the cloud to ensure stability. The system captures images taken inside the vinyl greenhouse and stores them in a database, and then downloads the images to the cloud to perform inference based on Yolo-v4 for detection, generating JSON files for the results. Analyze this file and send it to the database for storage. From the experimental results, it was confirmed that disease detection through object detection showed high performance in real environments like vinyl greenhouses. It was also verified that efficient monitoring is possible through the database

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.27-39
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• 2023

Detecting greenhouses from the remote sensing datasets is useful in identifying the illegal agricultural facilities and predicting the agricultural output of the greenhouses. This research proposed a methodology for automatically detecting greenhouses from a given Planetscope satellite imagery acquired in the areas of Gimje City using the deep learning technique through a series of steps. First, multiple training images with a fixed size that contain the greenhouse features were generated from the five training Planetscope satellite imagery. Next, the YOLO(You Only Look Once) model was trained using the generated training images. Finally, the greenhouse features were detected from the input Planetscope satellite image. Statistical results showed that the 76.4% of the greenhouse features were detected from the input Planetscope satellite imagery by using the trained YOLO model. In future research, the high-resolution satellite imagery with a spatial resolution less than 1m should be used to detect more greenhouse features.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.371-377
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• 2013

The government has been carrying out a project for supporting the rain shelter for hot pepper as part of measures stabilizing the demand and supply of hot pepper since 2012. However, the eaves height of single-span plastic greenhouses extensively used in farms is low, which are inappropriate for the rainproof cultivation of hot pepper. This study attempted to develop single-span plastic greenhouses which are structurally safe and have the dimensions suitable for the rainproof cultivation of hot pepper as well. The structure status of plastic greenhouses and restructuring wishes of 56 rainproof cultivation farms nationwide were investigated to set up the width and height of the plastic greenhouses. 53% of the plastic greenhouses currently in operation had a width of under 7 m and 64% of their eaves had a height of 1.5 m or less, which accounted for the highest rate. Mostly the width of 7.0 m was desired for the greenhouses and the height of 2.0 m for their eaves, so these values were chosen as the dimensions for the singlespan plastic greenhouses. After an analysis of their structural safety while changing the specifications of the rafter pipe in various ways, 5 kinds of models were suggested considering the frame ratio and installation costs. The 12-Pepper-1 model is a developed single-span plastic greenhouse for hot pepper in which a ${\emptyset}42.2{\times}2.1t$ rafter pipe is installed at an interval of 90cm and the models of 12-Pepper-2 through 5 are the other developed ones in which a ${\emptyset}31.8{\times}1.5t$ rafter pipe is installed at intervals of 60 cm, 70 cm, 80 cm and 90 cm, respectively. As a result of an analysis of economic feasibility of 12-Pepper-2 compared to 10-Single-3 in the notification of the Ministry for Food, Agriculture, Forestry and Fisheries, it turned out that there would be an increase in profits by about 1.2 million won based on one building of a greenhouse sized 672 $m^2$.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.1-8
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• 2009

The greatest and major cost for cut rose production during winter seasons in Korea is cost of heating the greenhouse. A study was conducted on a cost-efficient heating system to reduce expenses of cut rose growers in times of high energy prices. An infrared heating system utilizing radiant energy has an obvious advantage over other heating methods in that the energy is first used to raise temperatures of plants and other objects and subsequently that of the atmosphere, resulting in faster reaching to desired plant temperatures at a reduced heating cost. In this study the heating effect and heating cost saving of a nano-carbon fiber infrared heating system (NCFIHS) installed in cut rose greenhouses in Gimhae, Gyeongnam Province were analyzed comparatively. In addition growth, quality, and vase life of 'Orange Fresh' roses grown in greenhouses heated by NCFIHS against those grown in greenhouses heated by so called an electrical heating system. In greenhouses with a NCFlHS with a set point air temperature of $20^{\circ}C$, plant temperature was maintained at $1{\sim}2^{\circ}C$ higher than the air temperature, and temperatures of growing bed surface and root zone were maintained at $17{\sim}19^{\circ}C$ throughout cold winter nights. The cost for heating in NCFIHS was about 25 and 51% of that of an electrical heating system and a hot water heating system heated by petroleum, respectively. Growth of roses harvested in greenhouses with a NCFIHS was similar to those grown in greenhouses with an electrical heating system. However, cut roses with more intense petal and leaf colors and a longer vase life (fresh weight and amount of water uptake) were harvested in greenhouses with a NCFIHS as compared to those harvested in greenhouses with an electrical heating system.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.16-20
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• 2006

Four leguminous crops grown in greenhouses and fields in Korea were surveyed from 2000 through 2002. Sclerotinia rot most severely occurred up to $60\%$ in Phaseolus vulgaris grown in greenhouses but occurred as low as $0-0.5\%$ in that grown in fields. Incidence of the disease in Pisum sativum grown in greenhouses ranged $1-5\%$, and that in Vicia Java and Vigna sinensis grown in fields was $0.8\%$ and $2\%$, respectively. Symptoms of Sclerotinia rot commonly developed on stems and pods of the crops. A total of 59 isolates of Sclerotinia species were obtained from diseased stems and pods of the crops. All of the isolates were identified as Sclerotinia sclerotiorum based on their morphological characteristics. Eight isolates of the fungus were tested for their pathogenicity to four host crops by artificial inoculation. All of the isolates induced rot symptoms on stems of the host crops tested, which were similar to those observed in the fields. The pathogenicity tests revealed that there was no significant difference in the susceptibility to the isolates among the leguminous crops tested This is the first formal report that S. sclerotiorum causes the Sclerotinia' rot of the four leguminous crops in Korea.