• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.5
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• pp.601-610
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• 1986

The acoustic intensity in the very near field of a vibrating surface reveals information about the location of sound sources and sinks. A system model of tennis racket was developed from simultaneous measurement of excitation force, surface vibration and the near field sound pressure. The characteristics of structural dynamics were obtained by standard experimental modal analysis techniques while the sound radiation characteristics were determined by estimating the acoustic intensity. In this paper, the information about vibration behviour was obtained by acoustic intensity method and some, experiments for verification were carried out. Close correlation was found between experimentally determined acoustic intensity and vibration mode patterns of the tennis racket.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.1
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• pp.57-64
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• 1990

It is important in design of vertical pumps to consider arbitrary foundation excitation in addition to rotor vibration due to unbalance. In this study, a model of a vertical pump was developed for the analysis of its dynamic response. The vertical pump was modeled with lumped masses and springs which represent mult-cylinderical and rotor structure. A dynamic simulation program was developed and numerical calculation on the above mentioned problems were carried out.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.spc1
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• pp.169-175
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• 2004

동의보감에 수재되어 있는 약쑥은 식용뿐만이 아니고 한방에서는 출혈 및 지혈약으로 자궁출혈, 임신중의 출혈, 코피지혈 등에 효과가 크다고 알려져 왔다. 또한 부인병과 건위, 설사치료와 항암활성, HeLa cell에 대한 억제작용도 보고되어 있다. MeOH엑스가 HCl-EtOH유발법, $1\%$ 암모니아 수용액 유발법, HCl-aspirin 유발법등에 의하여 유발된 위 손상에 대하여 강한 억제 작용을 나타내고 있는데 이는 flavonoid의 일종인 eupatilin으로 확인된 바 있다. 이 물질이 5-lipoxygenase inhibitor ($ID_{50}=14{\times}16^{-6}M$) 작용과 prosta glandin synthase의 활성을 약간 억제한다고 보고되었다. 약쑥의 eupatilin과 jaceosidin을 분리하여 그 화학구조를 구명하였다. 이를 지표물질로 하여 HPLC 분석조건과 HPLC용 검체의 조제, 표준검량선을 작성하였다. 강화사자발쑥 100 g의 잎에는 eupatilin은 240 mg, jaceosidin은 10 mg함유되어 있고 싸주아리쑥에는 eupatilin은 330 mg, jaceosidin은 123 mg 함유되어 있음이 확인되었다.

• Journal of Bio-Environment Control
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• v.14 no.1
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• pp.15-21
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• 2005

This experiment was carried out to investigate the effect of ridge direction (south-north) on temperature and light intensity on early growth of oriental melon under east-west oriented vinyl house cultivation. The air-temperature of minimum between north and south-ridge in the tunnel of vinyl house was $12.5^[\circ}C\;and\;11.3^{\circ}C$ and that of maximum between north and south-ridge was $36.7^{\circ}C\;and\;34.7^{\circ}C$, respectively. The minimum and maximum air-temperature of north-ridge in the tunnel of vinyl house on Feb. 15 were $12^{\circ}C\;and\;2.0^{\circ}C$ higher than those of south-ridge, respectively. The intensity of daylight between south and north-ridge was similar during 9:00-10:30 a.m., that of south-ridge was higher than north-ridge during 10:30-11:30 a.m. and that of north-ridge was higher than south-ridge during 11:30-17:30. The plant growth after 55 days of planting on the north-ridge was prominent cultivation compared to south-ridge. The female flowering and first harvesting day were earlier in north-ridge than in south ridge. The marketable fruits rate and yields (kg/10a) were $6.7\%$ and 218kg higher in north-ridge cultivation than south-ridge, respectively. Differences of marketable fruit rate and yield (kg/10a) in each ridge were significant.

• Journal of Korean Society of Forest Science
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• v.90 no.2
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• pp.184-189
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• 2001

Multiple shoots were induced from in vitro shoot originated from winter bud of P. yedoensis from Jeju. Most explants grow in similar type among the five different media but affected by supplement of sucrose regardless of media. For mass-propagation various concentrations of BAP or $GA_3$ were treated in the medium respectively. BAP was very effective to produce multiple shoots and 3.5~9.5 shoots were formed on the explant. The shoots induced on the high levels of BAP have short internodes. No shoots were induced on the treatment of $GA_3$ but roots were induced on it. When $GA_3$ was supplemented with the medium containing BAP, multiple shoots were produced from the explants. The medium(WPM) containing with $0.5mg/{\ell}$ BAP and $4.0mg/{\ell}$ $GA_3$ was most effective to produce multiple shoots. When the explants were cultured for 8 weeks, 39.5 shoots were developed in average.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.122-127
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• 1983

Germination and seedling emergence of 40 barley cultivars and lines having been bred in Korea were studied under different water and salt stress conditions containing different sucrose and KC1 concentration in laboratory at Suweon. This study revealed that the barley cultivars and lines differed markedly in their emergence rate index(ERI), total stand(TS), coleoptile length, seedling height, top and root weight. Those characters of the most cultivars were progressively reduced as water and salt stress increased. Jogangbori, Dongbori 1, SB 77460 and SB 77415 were less sensitive to both stress and will be useful for breeding sources. ERI was highly correlated with TS, coleoptile length and seedling height. ERI and TS between two different solutions were correlated each other, and this study indicated that for screening the varieties or lines tolerant to water and salt stress, both ways were available and should be screened genetic materials with a good germination and emergence rate in I stress conditions.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.229-235
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• 2012

This study was conducted to investigate the climatic factors affecting bud phenology of Pinus densiflora provenances. Data were collected from Jungseon, Chungju and Jeju plantations which were parts of the 11 provenance trials established by Korea Forest Research Institute in 1996. The 36 provenances were included in this trial ($33^{\circ}30^{\prime}{\sim}38^{\circ}08^{\prime}$ in latitude and $126^{\circ}30^{\prime}{\sim}129^{\circ}20^{\prime}$ in longitude). The bud swelling date and bud burst date of the provenances were investigated from March to May in 2004 in two-day interval. The four geographic factors and fifteen climatic factors of the test sites and provenances were considered in this study. Canonical correlation analysis was conducted to examine the major factors affecting the bud phenology. Our results suggested that the major factors affecting the timing of bud swelling and burst are the differences in latitude, longitude, extremely low temperature (during December-February), extremely high temperature (during November-February) and annual mean growing days between test plantation and provenance. The provenances with lower winter temperature than that of plantation showed the faster bud swelling and bud burst. Based on these results, the implication on the seed transfer of P. densiflora was discussed.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.288-293
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• 2016

The study was performed to evaluate thermal insulation covering materials (TICMs) to protect peach trunks against freezing temperatures in winter season by investigating thermo-physical properties and practical thermal insulation effect of the TICMs which was made of white non-woven fabrics, yellow paper sheets, and waterproof fabric pads. Among the three TICMs, Waterproof fabric pad (double layer) possessed the best performance about thermal insulation rate and thermal resistance among three kinds of TICMs. Day thermal insulation effects of waterproof fabric pad, which prevent from temperature rise on the bark tissues of trunks during the day time, were $14.09^{\circ}C$. Night thermal insulation effects of them, which prevent from temperature decline on the bark tissues of trunks at night time, were $7.23^{\circ}C$. Waterproof fabric pad showed the highest day and night thermal insulation effects. Thus our results suggest that development of TICMs using waterproof fabric pad might be helpful to protect the bark tissues of trunks from freezing injury.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.225-234
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• 1997

This study was carried out to investigate the native distribution of wax myrtle (Myrica rubra) in Cheju Province and its propagation method. Wax myrtle is heavily distributed at 100 to 400m above sea level of Donhong-chun and Hyodon-chun which is bordered by Youngchon-dong of Seogwipo City and Haryeri of Namcheju county. BA, IBA, Kinetin, IAA, and GA3 were applied to promote rooting of cutting but were ineffective in promoting rooting. Treating cuttings with both AgNO,1 which removes rooting inhibitor, tannin and growth regulators such as BA, IBA and Kinetin were also ineffective in promoting rooting. Incubating seeds at 4$0^{\circ}C$ for 30 days resulted in 39％ germination. There was distinct difference in leaf shape between seedlings and mature trees.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.387-390
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• 2000

The experiment was conducted to investigate the effects of vine management and yield on fruit quality and bud burst of 'Campbell Early' grapevines in Hwaseong and Suwon area. The extreme value of minimum temperature of Hwaseong area, frequently causing cold damage, was lower than that of Suwon area in winter. Narrow spacing, overbearing, and poor vine management were observed in Hwaseong area, where the harvest time was delayed by 7 days compared with that of Suwon area. Total carbohydrate content of bearing mother branches was lower with 1.2~1.7%, and the percentage of bud burst was extremely lower at $-15^{\circ}C$. In Suwon area, there were no differences in cluster and berry size, but soluble solids content was lower and skin coloration was poorer when yield was high. Total carbohydrate content was lower when yield was high. The percentage of bud burst was lower at cold treatments below $-20^{\circ}C$. The results suggest that appropriate yield based on fruit quality is 2.3~2.6 MT/10a.