• Title/Summary/Keyword: 유향도

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Flow and Structural Response Characteristics of a Box-type Artificial Reef (상자형 어초의 흐름 및 구조응답 특성)

  • Kim, Dongha;Woo, Jinho;Na, Won-Bae;Yoon, Han-Sam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.26 no.3
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    • pp.113-119
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    • 2014
  • We carried out flow and structural response analysis of a box-type artificial reef (AR), which is made of concrete and structural steel. From the flow analysis, the wake region and drag coefficient were evaluated and accordingly, the structural analysis was performed to evaluate the stress and deformation of the target reef by considering the pressure field obtained from the flow analysis. The concept of wake volume was presented to quantitatively estimate the wake region and its variation according to flow direction and velocity. From the results, it is shown that the flow responses are only sensitive to the flow direction; the structural responses are sensitive to both of the flow velocity and direction although the magnitudes are negligible; and the wake volume became 3.52 times the AR volume with an optimum installation condition ($30^{\circ}$, flow direction) of the target unit.

Dynamic Behavior of Model Set Net in the Flow (모형 정치망의 흐름에 대한 거동)

  • Jung, Gi-Cheul;Kwon, Byeong-Guk;Le, Ju-Hee
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.33 no.4
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    • pp.275-284
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    • 1997
  • This experiment was carried out to measure the sinking depth of each buoy, the change in the net shape of the net, and the tension of sand bag line according to the R (from bag net to the fish court) and L (from fish court to the bag net) current directions and their velocity by the model experiment. The model net was one-fiftieth of the real net, and its size was determined after considering the Tauti’s Similarity Law and the dimension of the experimental tank. 1. The changes of the net shape were as follows : In the current R, the end net of fish court moved 20mm down the lowerward tide and 10mm upper part. So the whole model net moved up at 0.2m/sec. The shape of the net showed an almost linear state from bag net to the fish court at 0.6m/sec. In the current L, the door net moved 242mm down the lowerward tide and 18mm upper part. So the whole model net moved up at 0.2m/sec. The net shape showed an almost linear state from the fish court to the bag net at 0.5m/sec. 2. The sinking depths of each buoy were as follows: In the current R, the head buoy started sinking at 0.2m/sec and sank 20mm, 99mm at 0.3m/sec and 0.6m/sec, respectively. The end buoy didn't sink from 0m/sec to 0.6m/sec but showed a slight quake. In the current L, the end buoy started sinking at 0.1m/sec, and sank 5mm and 108mm at 0.2m/sec and 0.6m/sec, respectively. The whole model net sank at 0.5m/sec except the head buoy. 3. The changes of the sand bag line tension were as follows: In the current R, the tension affected by the sand bag line of the head buoy showed 273.51g at 0.1m/sec increased to 1298.40g at 0.6m/sec. In the current L, the tension affected by the sand bag line of the end buoy on one side showed 137.08g at 0.1m/sec increased to 646.00g at 0.6m/sec. The changes in the sand bag line tension were concentrated on the sand bag line of the upperward tide with increasing velocity at the R and L current directions. However, no significant increase in tension was observed in the other sand bag lines.

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Comparison of Immune Activities of Essential Oils from Juniperus rigida S. et Z. and Boswellia carteii Birew by Supercritical Fluid Extraction System (노간주나무와 유향나무의 초임계 공법으로 추출한 정유의 면역 활성 비교)

  • Mun, Hyoung-Chul;Park, Jin-Hong;Kim, Dae-Ho;Yoo, Jae-Eun;Kim, Jung-Hwa;Kim, Chang-Ho;Kim, Jong-Dai;Park, Young-Sik;Lee, Hak-Ju;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.12 no.3
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    • pp.243-248
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    • 2004
  • Essential oils from Needl Juniperrus seed and trunk (Juniperrus rigida Sieb.) and Olibanum resin (Boswellia carteii Birew) were extracted by a supercritical fluid extraction system (SFE) and immune activity of each essential oils were observed. The immune activities of each essential oil were compared. Essential oil from Olibanum resin enhanced the growth of human immune T cell up to 1.33 times, compared to control group. Each essential oils showed the potent inhibitory effect on the human cancer cell lines, and increased the secretion of cytokines, IL-6 and $TNF-{\alpha}$ from human B cell as well as the growth of human immune cells.

Breeding of Fragrant Yellow Phalaenopsis and Scent Pattern Analysis by GC/SAW Electronic Nose System (유향성 황색계 호접란 육성 및 전자코를 이용한 향기패턴 분석)

  • Been, Chul-Gu
    • Horticultural Science & Technology
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    • v.28 no.4
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    • pp.656-663
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    • 2010
  • In order to improve the consumer acceptance of fragrant yellow hybrids of $Phalaenopsis$ ($Phal.$), crosses between yellow hybrid varieties were made and the obtained hybrids were investigated for horticultural characteristics as well as difference in fragrance patterns. Cross combination of $Phal.$ Brother lawrence and $Phal.$ Brother saragold yielded good seedling population of 500 plants. Segregation was noticed in color density, spot and stripe patterns on yellow color base of petal and also in fragrance. Six lines with multi-branch on flower stalk and strong fragrance flower were finally selected. Volatile fragrance components were compared among $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids by GC/SAW electronic nose. In the derivative pattern of chromatogram and polar derivative pattern of fragrance, similar dominant peaks appeared on retention time 7-9 s and some hybrid lines had two strong peaks on retention time 20-25 s, respectively. Also in polar frequency pattern of fragrance obtained by $VaporPrint^{TM}$ image analysis among parent flowers and hybrids, an identical strong peak near 8 s of retention time was shown. This single fragrance component is considered a key element of fragrance in $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids. This peak could be used as a marker for the breeding of fragrance in $Phalaenopsis$.