• Weed & Turfgrass Science
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• v.2 no.4
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• pp.376-380
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• 2013

This research was carried out to establish a mass-production method and to develop ornamental Gramineae species as cash crops for famers as three species of ornamental grasses were used for seed treatment and plug production. Germination rates of Arundinella hirta were improved to 52.6% by soaking in 4% NaOCl for 60 min and 49.4% with 4% NaOH for 30 min. Germination rates of Panicum virgatum were 20.3% and 22.4% when treated with 4% NaOCl for 10 min and 2% NaOH for 60min treatment, respectively. Pennisetum alopecuroides showed germination rates higher than 98% with both 4% of NaOCl and NaOH for 60 min. When the same size of trays were used, Pennisetum showed faster plug formation in 21 and 30 days with 162 and 40 cell trays, respectively. Arundinella showed a similar trend with Pannicum in completing plug formation, those took 32, 41, and 44 days with the 162, 72, and 40 cell tray, respectively. Plug production was faster with smaller cells; however, total growing period was longer with larger cells in general.

• 대한공업교육학회지
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• v.33 no.2
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• pp.259-272
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• 2008

In order to improve the productivity and quality of boat's mold in leisure boat industry, the development of modelling and machining technology of leisure boat's plug is strongly required. The traditional lines drawing approach by hand required the designer to both create fair curves and to make sure that the curves matched up to each other in the three main drawing views: profile, plan, and section. However, one will find when studying lines drawings in books that the curves might look smooth and fair, but the lines do not agree exactly in the three views. Therefore, the 2 dimensional drawing data of leisure boat are transformed using 3 dimensional design s/w and CAM s/w. In addition, the leisure boat is designed with a 3 dimensional s/w. The NC cutting data are generated by the CAM s/w. The surface characteristics of machined surface are investigated at various cutting conditions such as spindle speed, feed speed, and cutting material.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.302-306
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• 2005

This Study was Conducted in 3 glasshouse to examine the Possibility for cultivation of plug seedlings using four growing media containing recycled PET-bottle-particles (PBT) as a medium component. Plug seedlings of 'Seokwang' tomato were grown in media containing $100\%$ PBT, $100\%$ peatmoss, or $50\%$ $PBT+50\%$ peatmoss. A commercial plug medium (Tosilee) was used as the control. All seeds were sown in 128 cell plug trays on July 12, 2004. Seedling growth was measured at 30 days after sowing. Percent seed germination was greater than 95% in all treatments. Plant height, shoot fresh and dry weights, leaf area, and hypocotyl length were the greatest in the control treatment. Root length and weight were the greatest in the $100\%$ PBT treatment, which had a medium pH of 7.3. Leaf area and shoot dry weight were greater in the $50\%$ $PBT+50\%$ peatmoss treatment, than in the $100\%$ PBT treatment, while they were the smallest in the $100\%$ peatmoss treatment. No toxicity symptoms caused by the use or PBT had been observed in any treatment. The results suggest a possibility of recycled PBT, a valuable reusable resource, to be used as a component for medium amendments in horticultural transplant production.

• Korean Journal of Organic Agriculture
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• v.10 no.2
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• pp.111-120
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• 2002

This study was conducted to investigate the effect of foliar application of Chitosan and seedling types on increasing the production of fall-growing potatoes(Solanum tuberosum) at the height of 250m from the sea in Jeju Island. The experiment main-plots consisted of four Chitosan applications, and subplots had three seedling types as cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot. The foliar application of Chitosan of 2000ppm was carried out 0, 1, 3, 5 times at intervals of ten days after ten days of transplanting. Plant height and top dry weight were significantly more vigorous as three to five application of Chitosan. In the small tubers(under 80g), the number of tubers and tuber yield were relatively increased in the seed potatoes planting plot and mine-tuber plug seedling plot, but the large tubers(over 80g) was higher in the cutting plug seedling planting plot. T-N content in leaves was increased as the number of application of Chitosan was increased. A similar tendency was shown in K, P Ca, Mg and Na. The growth and tuber yield in cutting plug seedlings, mine-tuber plug seedling planting plot and seed potatoes planting plot were effectively increased as three to five foliar applications of Chitosan was increased.

• Journal of Bio-Environment Control
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• v.12 no.1
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• pp.7-11
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• 2003

Cellular glass foam (CGF), the reprocessed glass, has a possibility to be used as a medium component in plug culture of horticultural crops due to the its excellent air and water permeability as comparable to perlite. An experiment was conducted to investigate growth of plug seedlings of Lycopersicum esculentum 'Segye' as influenced by irrigation frequency in various medium combinations of CGF (2.0-4.0 mm particle size) and peatmoss. Seeds were sown in 200-cell plug trays, filled with mixtures of CGF and peatmoss either at 33：67 or 25：75 (％. v/v) and were germinated on a fogged propagation bed. The irrigation frequencies used were one, two or three times per every two days. A commercial plug medium (Tosilee medium) was used as the control, and the irrigation frequency in the control was one time per day. Growth of seedlings, and medium pH and EC were measured at 33 days after sowing. The medium composition had little influence on overall growth of seedlings. Irrigation frequency very significant affected number of leaves, leaf area, chlorophyll concentration, fresh and dry weights of shoots and roots, and dry matter. Growth of seedlings was the greatest with the highest irrigation frequency in the 25% CGF＋75% peatmoss mixture.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.239-251
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• 2023

The aim of this study is to evaluate the effect of noise-filtering earplugs on the hearing ability of dentists wearing them during noise-induced dental procedures. Pure tone audiometry and distortion product otoacoustic emission (DPOAE) tests were conducted at the initial visit and 1 year later to evaluate the hearing ability of the participants. As a result of the study, the pure tone average of the group wearing earplugs decreased significantly compared to the group not wearing earplugs, indicating an improvement in hearing. However, the signal-to-noise ratio of the DPOAE tests did not show a significant difference. These findings suggest that noise-filtering earplugs may have some effectiveness in preventing hearing loss. However, since the 1-year observation period may not be adequate to identify changes in hearing, a follow-up study with an extended follow-up period is necessary.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.11a
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• pp.40-45
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• 2001

최근 들어 육묘시설의 양적 증가와 육묘 기술 수준의 향상에 힘입어 플러그묘의 보급이 확대되고 있다. 더구나 육묘와 재배의 분업화가 진행되고, 고품질 묘의 안정된 수급이 대한 관심이 늘어나면서 육묘 산업에 대한 비중이 점차 증가하고 있다. 국내에 설치되어 있는 모든 육묘시설은 개방형 묘생산 시스템으로서, 육묘시설 내의 환경이 외부 기상 조건과 밀접한 관계를 이루며 변화하는 특성을 갖는다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2006.05a
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• pp.308-312
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• 2006

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.305-310
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• 2003

옥내에서 사용하는 300V 이하의 소형전기기구의 전원선으로 사용되는 비닐코드는 가요성 및 절연성이 우수하며 구조는 연동선을 꼬아 합친 것 위에 절연체(PVC)로 절연한 것이다. 비닐코드에서의 화재발생 부위는 플러그 부분, 연장코드 부분, 연장코드와 부하기기의 접속부 부분에서 발생하며, 화재 원인은 접속 및 접촉불량, 반단선, 방열불량에 의한 전선과열, 플러그 몸체 및 피복 절연물의 절연열화, 과전류(과부하) 등에 의해 선간단락이나 지락사고 등으로 화재가 발생한다.(중략)

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.279-282
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• 2004

국악 샘플링 신디사이저 VST 플러그인 프로그램 보호방법은 국내 최초로 한양대학교 뉴미디어 뮤직 전공에서 개발된 국악기 샘플링 신디사이저의 배포를 위하여 개발되었다. 소프트웨어가 설치된 컴퓨터의 고유인식 번호를 배포자의 서버로 전송, 암호화된 인증키를 최종 사용자에게 다시 부여하는 방식으로, 문화 컨텐츠 진흥원의 지정과제인 "국악연주 가상환경용 입체음향효과 및 국악기 음 합성기술개발"의 사업화에 큰 도움이 되기를 바란다.