• Title/Summary/Keyword: vessel elements

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Transverse vibration reduction at navigation bridge deck of the shuttle tanker using structural intensity analysis (진동 인텐시티 해석을 통한 원유운반선의 거주구 횡방향 진동 저감 연구)

  • Kim, Ki-Sun;Kim, Heui-Won;Joo, Won-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2012.10a
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    • pp.251-255
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    • 2012
  • Structural intensity has been mainly utilized to identify vibration energy flow in a vessel. In this paper, the structural intensity of a shuttle tanker subjected to H-moment of the main engine was calculated using a finite element model. From the analysis, it was found that the top-bracing elements, which support the main engine onto the hull structure to prevent the excessive transverse vibration of the main engine, play the role of the dominant path and sink for vibration energy flow from the main engine. Therefore, the structural intensity was controlled by the modification of stiffness and damping characteristics of the top-bracing elements. As a result, it is observed that the transverse vibration level at the center of navigation bridge deck decreased after the control of structural intensity.

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A Study on Theoretical Background Relationship of Blood Vessel Pressure Massage and Skin and Management Method of Blood Vessel Pressure Massage for Skin Care (피부미용과 관련된 한방미용경락의 이론적 배정 연구)

  • Choi, Jong-Mi;La, Young-Sun
    • Journal of the Korean Society of Fashion and Beauty
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    • v.2 no.1 s.1
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    • pp.5-13
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    • 2004
  • This study was analyzed on relationship of blood vessel pressure massage and skin and management method on blood vessel pressure for skin care with Yin-yang 5 factors theory, Yin-yang 5 factors theory of blood vessel pressure massage with related Korean medicine is essential for descriptions of the physiology of human body and disease. Six elements(wind, heat, fire, dryness, wetness, and cold) and seven emotions(anger, happiness, thought, worry, sadness, surprise, and fear) effected on skin care and the five viscera and the six stomach. Blood vessel pressure massage related with skin consists of the five viscera and the six stomach and is improved blood circulation and is retarded aging of skin by controls of hormone and free nerve system. Blood vessel pressure massage for skin care improved in the intestine system and blood circulation and got healthy. The blood vessel pressure massage treatment of beauty art can aid the function of bio-rhythm of a human body and make our body health by healing the problems of the five viscera organs and the six stomach. It also help circulate of the blood flow and vigor. The study expects the related researches to improve the various treatments through this treatment. The researcher encountered many problems with the lack of concerned materials and former studies but expects this study to be a study to retard aging the skin and prevent the diseases through the study of the blood vessel pressure massage.

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Wood Anatomy and Phylogeny of Laurus ( Lauraceae )

  • Heo, Kweon
    • Plant Resources
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    • v.1 no.2
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    • pp.121-125
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    • 1998
  • Wood and bark structure of Laurus, which is considered as an important spice resources was characterized by several transitional and advanced features. Annual rings are distinct: vessel elements are moderately short and narrow, both simple and sealariform perforation plates. alternate intervascular pitting; irregularly septate fiber are present; parenchyma strands are scanty paratracheal: rays are both homogeneous and heterogeneous with multiseriate: phloem rays are dilated. Comparisons with other genera of Lauraceae suggest that Laurus is transitional and advanced state in evolutionary trends in the family.

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Comparative Wood Anatomy of Stem and Root in Korean-grown Yellow-poplar (Liriodendron tulipipfera L.)

  • Lee, Mi-Rim;Eom, Young-Geun
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.5
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    • pp.406-419
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    • 2011
  • This study was carried out to offer basic information on the wood anatomy of domestic yellow-poplar (Liriodendron tulipifera L.), a new plantation species selected by Korea Forest Service as one of the promising hardwood and bioenergy sources of the future, through comparison of stem wood with root wood in the qualitative and quantitative features. In the qualitative anatomical features, growth rings were distinct in stem wood but relatively less distinct in root wood. And stem wood appeared to have pores in radial multiples of 2 to 5, sometimes clusters but root wood to have pores in radial multiples of 2 to 3, rarely clusters. And numbers of bars in scalariform perforation plates were somewhat numerous in vessel elements of root wood than in those of stem wood. Interestingly, on the other hand, more extraneous materials in the wood rays of tap root than in those of lateral root and stem were confirmed in the chemical composition analyses. In the quantitative anatomical features, pore densities were significantly greater but vessel elements were considerably narrower in stem wood than in root wood. Vessel elements and wood fibers of root wood were considerably longer than those of stem wood. Rays were somewhat more numerous in stem wood than in root wood, and only ray heights of stem wood were more or less greater in cell numbers but both ray heights and widths of stem wood were lower in dimension than those of root wood. The anatomical differences between stem wood and root wood were thought to be associated with different growth environments between the stem above ground and the root below ground.

An Anatomical Comparison of the Secondary Xylem in the Branch, Stem and Root of Salix glandulosa and Quercus variavilis (왕버들과 굴참나무의 뿌리, 줄기 및 가지에 있어서 이기목부(二期木部)의 해부학적(解剖學的) 비교(比較))

  • Ryu, Ha Yong;Soh, Woong Young
    • Journal of Korean Society of Forest Science
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    • v.77 no.3
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    • pp.283-293
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    • 1988
  • Anatomical features of the secondary xylem were described in the branches, stems, and roots of Salix glandulosa and Quercus variavilis. In Quercus variavilis, the stem shows ring-porous wood, while the root shows diffuse-porous wood. In both species, it is found that the boundaries between the growth rings are not well defined in the roots. Both vessel elements and fibers are the longest in the roots followed by the sterns and the branches in turn and diameter of vessel elements shows the same trend. In cross section, the number of vessels per unit area are the longest in the branches followed by the stems and the roots in turn as well. Perforation plates are simple in both species and their angles are wide in the root, intermediate in the stems, and narrow in the branches. In tangential section, height of rays is taller in the roots than in the stem and branches.

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Anatomical Characteristics of Major Korean Ash Species (한국산 물푸레나무속(屬) 주요 수종의 해부학적 특성)

  • Hwang, Won-Joong;Kwon, Goo-Joong;Park, Wan-Geun;Bae, Young-Soo;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.2
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    • pp.79-86
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    • 2002
  • Anatomical characteristics of Mulpurenamu (Korean ash, Praxmus rhynchopbylla), Deulmaenamu (Manshurican ash, Fraxinus mandsburica) and Sheamulpure (Sieboldiana ash, Fraxinus sieboldiana) grown in Korea were examined by an optical microscopy and an image analysis. Some characteristics such as boundary of annual rings, shape and size of vessel elements, arrangement of axial parenchyma cells in cross section, and cell volumetric composition showed significant differences between the sample species. In radial variation of elements, fiber length and vessel size increased from the pith for about 10 to 15 years and then reached a more or less constant. The results of this study can be used for identification of wood and indices of wood quality in Fraxinus spp.

An Empirical study on improvement of operation for feeder vessel route between Busan and west coast of Japan

  • Kim, Sang-Youl;Kim, Dong-Jin;Ryoo, Dong-Keun;Yoo, Yong-Joo
    • Journal of Navigation and Port Research
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    • v.35 no.7
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    • pp.605-611
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    • 2011
  • In this paper, practical problems for current feeder service between Busan port and west coast of Japan were extracted through in depth interviews with Japanese feeder vessel companies, shippers, and port authority based upon which major criteria (elements) for improvement of the feeder network are structured in hierarchic order and weighed relative importance through AHP method. From the questionnaire answered by Korean and Japanese port users and experts the weights of criteria were calculated and the shipping service was ranked the first by both parties with 0.235 and 0.217, respectively. The port service and support system ranked the second and the third, whereas the port marketing was shown to be the lowest of all. Considering the overall weights, the increase in a port loading and unloading speed of port service was followed by provision of dedicated deck for feeder vessel of port facilities for Korean respondents. Therefore, speed up of the port operations and providing docks for feeder vessel are to be firstly provided for more efficient feeder operations, which would be the basis for the construction of optimal transportation network.

Alkali-Swollen Morphology of Native Cellulose Fibers

  • Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.2
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    • pp.16-22
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    • 2007
  • The behavior of ramie fibers and some wood elements in the early stage of alkali swelling was examined. When the fibers were treated with alkali solution, they significantly shrank in length and swelled in wall thickness. Ramie fibers showed a shrinkage averaging 23% in length and a swelling averaging 92% in width in 100 seconds treating time. Dimensional changes showed different fashion in each element of woods. The tracheids of latewood especially in Pinus densiflora and Larix kaempferi woods swelled intensively and showed balloon swelling, but in the case of Cryptomeria japonica, it was hardly observed. The swelling morphology of libriform fibers was similar to that of tracheids. The walls of vessel elements and parenchyma cells also swelled considerably in thickness but, no balloon swelling was found in both elements. The differences of swelling in different elements can be interpreted in terms of the differences of organization and/or chemical components of the cell walls.

Micro Structural Changes in Juvenile and Matured Wood of Populus tomentiglandulosa T. Lee

  • Lu, Sun;Ahmed, Sheikh Ali;Chong, Song-Ho
    • Journal of the Korea Furniture Society
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    • v.17 no.3
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    • pp.29-36
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    • 2006
  • Juvenile and matured wood of Populus tomentiglandulosa species of Salicaceae native grown in Korea was observed by FE-SEM and optical microscope. Species is characterized by mostly diffuse-porous, simple perforation plates, polygonal alternate non-vestured intervessel pit, medium length of vessel elements and fibres, non-septate very thin walled libriform fibres and exclusively uniseriate procumbent rays. Axial parenchyma was absent or extremely rare. Vessel and fibre length were longer in both matured and juvenile latewood than those of earlywood. Ray cell lumen diameter, ray length, number and diameter of endwall pit in ray cell, endwall pit, number and diameter of pit in lateral wall of one ray parenchyma cell, vessel ray pit number and diameter vary from juvenile early and latewood to matured wood.

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Systematic Studies on Some Korean Woody Plants - A Comparative Wood Anatomy of Magnoliaceae, Winteraceae and Schizandraceae - (한국산 목림식물에 대한 계통분류학적 연구 - 목련과, 붓순나무과 및 오미자과의 비교목부해부 -)

  • 소웅영
    • Journal of Plant Biology
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    • v.28 no.4
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    • pp.271-284
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    • 1985
  • Anatomical characters of secondary xylem in the trunk of Magnoliaceae, Winteraceae and Schizandraceae, including six genera and eleven species grown naturally in Korea, were studied to elucidate the relationship between genera or families. It is considered that among these families specialization in the perforation plate, the angel of end wall to the vessel axis, and diameter of vessel element, is in the order of Winteracae, Magnoliaceae, and then Schizandraceae. In Winteraceae, vessel elements have wholly scalariform perforation plates with very numerous bars. Among Magnoliaceae the peroration plates are scalariform with very numerous bars in Michelia, with few bars in Liriodendron, and with few bars or simple in Magnolia. In Schizandraceae, Schizandra shows scalariform perforation plates with few bars or simple perforation plates, and Kadsura shows almost simple ones.

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