• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.619-630
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• 2017

In recent years, not only the cultivation area of Jujube in Korea but also the number of pest species has increased. The farmers farming environmentally friendly are in great difficulty because there are no effective control devices. This study was conducted to investigate the control effect of the insect screen net on three pest species (Apolygus spinolae, Dasineura sp. and Carposina sasakii) in Jujube orchard when the pests were blocked by insect screen net. For the first and second surveys, the damage rates by A. spinolae were 9.06, 13.95% in 50 mesh, 4.75, 10.17% in 25 mesh, 5.68, 11.84% in 18mesh mesh of insect screen net and 21.6, 36.34% in untreated insect screen net, respectively. The damage rates by Dasineura sp. were 0.54, 0.13% in 50 mesh, 0.93, 2.84% in 25 mesh, 1.05, 13.45% in 18 mesh mesh of insect screen net and 11.1, 26.65% in untreated insect screen net. Carposina sasakii were completely blocked in all the treatments. Damages on Jujube were not observed by insect screen net. Therefore, insect screen net is effective on insect pest control for Jujube.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.46-54
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• 2016

BACKGROUND: The tobacco whitefly(Bemisia tabaci Gennadius) and western flower thrips(Frankliniella occidentalis Pergande) seriously damaged to several greenhouse crops and transmitted plant viruses such as the Tomato Yellow Leaf Curl Virus(TYLCV) and Tomato Spotted Wilt Virus(TSWV). Objective of this study was to elucidate exclusion effects of insect screen nets by various hole sizes and colors for control of the two insect pests in controlled environments such as a closed plant production system.METHODS AND RESULTS: The exclusion effects to various hole sizes of three other colors with 30 individuals of two insect pests was evaluated. B. tabaci was not showed not difference to different colors and sizes. F. occidentalis showed that 0.2 mm black screen was the most effective exclusion than other colors of 0.6 and 0.8 mm.CONCLUSION: The two insects were different reponses to various hole sizes of white and other color screen nets. It was proved that the 0.4 mm white screen net used in this experimental condition was suitable for exclusion of B. tabaci and 0.2 mm black forF. occidentalis.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.270-271
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• 2015

본 논문은 추락 방지장치가 형성된 창문에 관한 것으로, 일반적인 형태의 공동주택 여닫이 창문은 사각틀 형태로 된 창틀의 내 창문이 슬라이드 가능하게 끼워져 있고, 창문을 개방 시, 창틀에 해충방지용 방충망이 설치되어 있지만, 종래의 방충망은 구조적으로 매우 취약하여 찢어지거나 휘면서 창틀로부터 쉽게 이탈되어 쉽게 추락사고가 발생하였다. 이러한 문제점을 해소하기 위해서 본 기술을 적용한 창문 설치 시, 개방했을 경우에만 체인 안전망이 형성되고, 창문을 닫았을 경우에는 체인 안전망이 창틀 또는 창문틀에 수용되어 보이지 않게 되어 미관을 해치지 않으면서도 추락 사고를 방지하여 안정성을 보장하는 효과를 거두었다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05c
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• pp.61-64
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• 2009

The number of apartment houses has accounted for more than 50% of all domestic residential types in Korea since 1980s. However, the apartment house has environmentally disadvantageous conditions such as highly residential-density and potential falls by children aged seven years and under through windows. In this study, we aim to suggest some ideas to improve domestic performance assessment methods and criteria of window Insect screens for protection on security and fall prevention by analyzing domestic standard with several overseas codes related to the screens for windows.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.23-27
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• 2013

Investigations were conducted to prevent entrance of Bemisia tabaci (Gennadius) with very fine mesh nets. B. tabaci vectors tomato yellow leaf curl virus in tomatoes. B. tabaci could be completely prevented to penetrate into an 83 mesh net, though few of them passed the 60 mesh net. An independent 60 mesh net cage was built within one of the three interconnected common plastic greenhouse ($21.0{\times}18.3m$) in order to find its usefulness as a crop protection tool from insect pests. TYLCV infected tomato plants were not detected, though a few eggs of B. tabaci and mines of Liriomyza trifolii (Burgess) were detected locally at the entrance of the sliding door. There were practically no significant differences between treatments of nets and the conventional plant height, leaf length and width, number of floret clusters, sugar brix, and product yield. In viewpoints of commercialization, it could be considered highly prospectful to apply to the nets to glasshouses or other greenhouses in which the growing period of crops is long, if the nets were used in the openings of sides, ceilings, and entrances of the greenhouse. However, it might be necessary to take preventive measures for occurrences of insect pests living in soil, temporarily or permanently, as well as high humidity diseases.

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.175-176
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• 2015

봄철 황사나 대기오염으로 인하여 실내에 오염된 공기가 유입되고 있다. 이를 정화하기위해 현재 실내에서는 공기청정기를 사용한다. 그러나 기존의 공기청정기는 이미 실내공기가 오염되었을 때 작동한다. 이를 보완하고자 본 논문에서는 방충망형 오염공기 차단기를 제안하였다. 방충망형 오염공기 차단기는 방충망에 고압의 DC 전압을 인가하여 코로나현상을 일어나게 하도록 만든 장치이다. 코로나 현상이 일어나면 주변 공기가 이온화 되는 원리를 이용하였다. 고압의 DC 전압을 발생시키기 위해 Full-Bridge 인버터를 이용하여 LC공진으로 변압기의 1차측 전압을 상승시켰고, 권선비를 이용하여 변압기 2차측 전압을 승압하였다. 마지막으로 배전압 정류회로를 설계하여 최종 DC전압을 생성하였다. 실험을 통해 제안한 방식의 유용성을 검증하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1653-1660
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• 2004

This study was conducted to investigate seasonal changes of microbiological counts and sanitation state on the surface of food service facilities and utilities of elementary schools in Busan area. Samples swabbed using sponge were collected from the surface of food service facilities and utilities, that is ceiling, wall, floor, trench, grease trap, hood, pest control net and dumb waiter, and analyzed by measuring the total plate, coliform and Salmonella spp. count. The total plate counts at foodservice facilities and utilities except ceiling and wall were ranged from 10$^4$∼10$^{6}$ CFU/100 $\textrm{cm}^2$. The coliform counts were ranged from 10$^2$∼10$^4$ CFU/100 $\textrm{cm}^2$ at foodservice facilities and utilities except ceiling. The grease trap was the severely contaminated facility. It was indicated that the sanitary condition at the foodservice facilities and utilities except ceiling and wall should be improved promptly. As a result of investigating the seasonal changes of microbiological counts, floor, trench, grease trap and dumb waiter should be carried out disinfection before foodserving everyday in summer season, and the disinfection frequencies of wall, hood and pest control net should not be less than three times per week. In winter season floor, trench, and dumb waiter should be carried out disinfection after foodserving, grease trap should be carried out disinfection before foodserving everyday and the disinfection frequencies of wall, hood and pest control net should not be less than twice per week.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2007.05a
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• pp.123-126
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• 2007

• Textile Coloration and Finishing
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• v.2 no.3
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• pp.65-75
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• 1990

유리를 압출하여 필라멘트형으로 제조하면 많은 소비자들의 요구를 충족시킬 수 있는 장식용 섬유로서 유용한 방적 재료가 얻어진다. 또한 유리의 고강도와 고탄성률을 고려하여 많은 산업용 직물과 복합재료의 보강재료에 이용된다. 본고에서는 유리섬유의 제조, 분류, 조성, 성질, 특성 등에 대해서 설명하고, 가공측면에서 표면처리 기술, Pre-preg의 제조와 용도, 필터백의 특징과 응용, 유리커튼의 특징과 제조, 방충망의 제조, 고무보강 기술에 대해서 언급하고저 한다.

• 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.