• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.877-885
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• 1993

Three types of solar grain dryers, namely , the solar grain bin dryer, the solar greenhouse rotary drum dryer and small scale solar green house tray dryer, have been tested. The results showed that each type of solar grain dryer has its feature. These solar drying units have three main advantages : (1) Required commercial energy to remove 1Kg moist from rough rice is only 5.3% to 15.8% of the energy consumed by common heated dryer : 2) The area of solar drying system is only about 10% of the area of the sunny ground to give equal drying capacity ; (3) There are good drying quality in the moisture uniform , germination percentage, and grain color.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.340-341
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• 2010

A computational study to capture the flow around a floor mounted greenhouse shaped HAWT model was performed using the commercial software PowerFLOW 4.2b. The simulation kernel of this software is based on the numerical scheme known as the Lattice Boltzmann Method (LBM), combined with an RNG turbulence model. Simulations were performed at 60 and 140 km/h free stream air speeds. Selective results from these computational simulations are presented to show the capability of this numerical approach to predict the aerodynamics and aeroacoustics characteristics of the 3-D flow field around the HAWT model.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.606-609
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• 2009

Development of renewable energy is very important because of environmental problems caused by greenhouse effect. This is due to the use of fossil fuels which has serious consequences. Therefore, development of small hydropower can be a good countermeasure for the problems. The small hydropower is clean energy because the small hydropower generates few $CO_2$. Moreover, as the energy density by the small hydropower is high, it is economical for a society which wants to introduce the system. The purpose of this study is to improve the turbine performance. This study is about tubular-type hydro turbine among renewable energy that is based using the different water pressure level in pipe lines. The analysis was performed using the commercial CFD code ANSYS-CFX.

• International Journal of Computer Science & Network Security
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• v.24 no.6
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• pp.171-179
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• 2024

Decentralized energy production without greenhouse gas emissions from renewable energy sources despite their advantage and environmental impact suffers from the problem of intermittent and fluctuating supply depending on weather conditions. To overcome this problem, energy storage is essential to enable reliable and continuous supply of the load. Hydrogen is one of the most promising energy storage solutions because it is easily transportable and can be used as fuel or as a raw material for the production of other chemicals.In this article, we will focus on hydrogen energy storage techniques using photovoltaic systems. We will review the different types of hydrogen storage structuresfor several applications, including residential and commercial buildings, as well as industry and transportation (electric vehicles using PEFMC fuel cells).

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.255-257
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• 2014

This study was conducted to determine the attractive effects of Plutella xylostella adults to light emitting diode (LED) trap in greenhouse and compared with those of no light trap and black-light which is typically used in commercial luring lamp. The green LED trap captured more P. xylostella when compared with black-light trap, whereas the no light trap was a little attractive to P. xylostella adults. These results indicated that the green LED traps could be used for environmental insect pest control.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.2
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• pp.57-65
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• 2010

To determine the static buckling loads and evaluate the structural performance of slender steel pipe-arches such as for greenhouse structures, a series of modal tests using a fixed hammer and roving sensors was carried out, by providing no load, then a range of vertical loads, on an arch rib in several steps. More attention was given to an internal arch where vertical and horizontal auxiliary members are not placed, unlike an end arch. Modal parameters such as natural frequencies, mode shapes and damping ratios were extracted using more advanced system identification methods such as PolyMAX (Polyreference Least-Squares Complex Frequency Domain), and compared with those predicted by commercial FEA (Finite Element Analysis) software ANSYS for various conditions. A good correlation between them was achieved in an overall sense, however the reduction of natural frequencies due to the existence of preaxial loads was not apparent when the vertical load level was about up to 38% of its resistance. Some difficulties related to the field testing and parameter extraction for a very slender arch, as might arise from the influences of neighboring members, are carefully discussed.

• The Plant Pathology Journal
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• v.15 no.3
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• pp.162-167
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• 1999

Integration of microbial antagonists with fungicides was tried to control the gray mold caused by Botrytis cinerea on pepper in greenhouse conditions and to reduce fungicide uses. All of the selected bacterial antagonists, Bacillus amyloliquefaciens BL3, Paenibacillus polymyxa BL4, and Pseudomonas putida Cha94, completely inhibited the conidial germination of B. cinerea until 30 days after treatment. However, bacterial colonization of pepper phylloplane was poor in BL4, while the other bacterial isolates and the fungal antagonist Trichoderma harzianum TM colonized well on the phylloplane, maintaining the population density of 104-105 cfu/g until 15 days after microbial treatments. Out of 13 kinds of selected fungicides used for gray mold diseases, polyoxin B and BKF 1995 showed the most discriminatory activity on the fungal growth between B. cinerea and TM. TM grew readily on the media containing those fungicides, while B. cinerea showed poor or no mycelial growth on them. The selected fungicides and antagonists alone reduced incidence of gray mold on pepper, showing disease indices of about 2.4 to 3.0, while its was increased up to 4.2 in the untreated control. Alternate treatments with the antagonists and 2-fold diluted fungicides inhibited the disease incidence as much as the antagonists or fungicides alone, and reduced the secondary inoculum more than the single treatments. This suggests that integration of antagonists and fungicides may be an efficient way to reduce fungicide sprays with reliable control efficacy of the disease. However, there was not much difference in the early and mid-term disease progress among the treatments and the untreated control, probably due to extremely favorable environmental conditions for the disease development in this experiment.

• Korean Journal of Medicinal Crop Science
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• v.9 no.3
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• pp.220-224
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• 2001

To obtain the basic information for commercial process and high quality production of Saururus chinensis, the yield and the contents of available component were determined at different compost application amounts and cultural methods. Fresh weight of aerial part was increased by increasing of the compost application amounts. The contents of quercetin, quercitrin and tannin were the highest in the compost 2,000kg/10a. Fresh weight of aerial part at different cutting times was no difference between one harvesting/year and two harvesting/year in S. chinensis. On occasion of two harvesting/year, the contents of component was more collected on July 16 than collected on October 16. Fresh weight of aerial part was less in the field than in the greenhouse culture method, but the contents of quercetin, quercitrin and tannin were more in the field than in the greenhouse culture method.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.553-558
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• 2010

To solve the problems of the low combustion activity of Korean anthracite and the abundant loss of unburned carbon in fly ash, pellet coal was fabricated from coal fines and fly ash, and the mixed combustion of coarse coal with the pellet coal was examined in the circulating fluidized bed combustor of a 0.1 MW scale test unit. In the combustion of the raw coal only, the significant amount of coal fines was entrained, resulting in overheat at the top of the combustor. With the coarse coal that most fines were eliminated, however, the combustion temperature was maintained stable. The mixed combustion of coarse and raw coals was also feasible even though it often went unstable. The mixed combustion of the coarse coal with the pellet coal was as stable as the coarse coal combustion, showing a promise that the combustion of the Korean anthracite in commercial circulating fluidized bed boilers could be further enhanced.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.431-437
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• 2016

This study was carried out to investigate pests and their damage caused to commercial greenhouse strawberries in Jeju from 2013 to 2016. A total of 8 orders, including 31 species, of pests were found. Among them, the major pests were Tetranychus urticae, Frankliniella occidentalis, and Aphis gossypii. Although Trialeurodes packardi and Empoasca vitis were sometimes severely damaged strawberries, their frequency of occurrence and damage caused increased gradually. Of lepidopteran pests, Spodoptera litura showed the highest occurrence and damage. Although Helicoverpa armigera was showed a low occurrence frequency, it caused severe damage. We discussed the seasonal occurrence patterns of four pests-F. occidentalis, the alate A. gossypii, T. packardi and E. vitis-monitored by yellow-colored sticky traps.