• Applied Microscopy
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• 제28권2호
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• pp.159-170
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• 1998

The glandular secretory system of the capitate gandular trichomes in leaf of Thymus quinquecostatus Celakovsky was examined by transmission electron microscope. The glandular trichome was consisted of three cell layers; an basal cell layer, a stalk cell with single-celled intermediate layer and a discoid secretory layer with thickened cuticle. The secretory cell was dense, rich in mitochondria, rER, plastds, Golgi complex and had many vesicular structure. Typical plastids with reticulate body and plastoglobule were present in glandular trichome. The tytoplasm of secretory cell was filled with osmiophilic secretory materials. The secretory vesicles, originated from Golgi complex, appeared as membrane bounded vesicles and secreted to the outer wall surface. The presences of well developed rER, mitochondria, Golgi complex, and membrane-bounded vesicles fused with plasmalemma in the secreting cells indicate that the granulocrine mechanism of secretion was occurring in T. quinquecostatus. Subcuticular cavity was developed between the cuticular layer and the secretory cell wall, and it formed above the secretory cell upon separation of cuticle-wall.

• 한국재료학회지
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• 제13권11호
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• pp.742-748
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• 2003

The structural parameters such as Lc, La and d of $CO_2$activated isotropic carbon fibers(ACFs) were obtained from XRD in order to understand a development mechanism of micropores. And the structural parameters were compared with specific surface area(SSA) data. The $d_{002}$, Lc, and La of the original fiber were measured to be 4.04$\AA$, 6.2$\AA$, and 23.6$\AA$, respectively. Carbonization of outer-parts and oxidization of inner-parts of the original fibers were far from completeness. It was observed that the structural changes of the ACFs during activation take place severely, therefore the carbonization and the oxidization of the fibers take place simultaneous with pore developments. The $d_{002}$ of the ACFs was increased to be 2.80$\AA$, and the La of the ACFs was decreased to be 17.0$\AA$ by activation. It was shown that the pores are developed continuously from the outer-parts to the inner-parts of the fibers, therefore the SSA increases as a result of the development of pores fully to the inner-parts of the fiber when the burn-off degree was over :39%. It seems that the (002) planes of crystallites contribute to the micropore wall related to the super high SSA.SSA.

• 소성∙가공
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• 제12권3호
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• pp.208-213
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• 2003

The methodology to design initial blanks considering the reduction of both springback and flange trimming amounts is studied. Three dimensional forming analysis of a trial blank Is first carried out using FEM and the tentative Initial blank shape is then determined by cutting the outer edge of the trial blank whose shape is nearly matched with the trimming line. During the shaping the blank edge, tile movement of blank outer line is described with random variables to reduce the sensitivity of initial blank geometry. After performing 2-D FEM forming and springback simulations for selected sections and optimizing the trimming and springback amounts in terms of section length of the blank, the initial blank is finally determined. In order to see tile springback reduction in the initial blank determined by the proposed method, a stepped s-rail is stamped and the sppingback is measured. The springback of newly designed initial blank of stopped s-tail is tremendously reduced.

• KIEAE Journal
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• 제13권6호
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• pp.121-128
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• 2013

This study attempted to explore the MC design methods of modular construction using discontinuous double module grids and further, the design methods of walls. Modular construction is generally characterized with multiple units called modules with a module dimension of 3M(300mm) appearing in the form of double grids. The discontinuous double grids including correction values and gap values occurs inevitably in the modular construction where units are joined horizontally. Therefore, it is desirable to carry out the MC design taking into account these discontinuous double grids. In this study, the MC design was applied to the plane of wooden houses in modular construction, going through a process of setting the size of pillars and inside dimensions, of determining the dimension of discontinuous double grids that occur during the assembly of units, and of setting the dimension of outer walls in conjunction with the derived dimensions. The dimension of outer walls was applied differently depending on the range of regional use by analyzing the energy performance with the materials used. Consequently, the materials and components of factory-produced buildings can be used directly without processing, and the suitability of the outer wall design can be pre-determined by previewing the calculation of the cross-sectional configuration and heat transmission coefficients of outer walls in modular construction, allowing to be used as a decision-making tool of design.

• 식물조직배양학회지
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• 제25권6호
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• pp.495-500
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• 1998

인삼(Panax ginseng C. A. Meyer) 캘러스로부터 분리한 원형질체를 배양하면서 배양시간에 따른 원형질체의 미세구조 변화와 원형질막 표면을 전자현미경으로 조사하였다. 3일 동안 배양된 원형질체에서는 조면소포체, 리보좀, 골기체, 미토콘드리아, 전색소체 등의 세포기관들의 수가 증가하였고 미소관도 관찰되었다. 골기체 주변에는 많은 골기소낭들이 형성되어 세포질 전반에 존재하였고, 이들 소낭들은 원형질막 바깥으로 돌출되어 돌기를 형성하기도 하였다. 소포체에서 유래된 액포속에는 액포의 함입에 의하여 골기소낭들이 들어 있는데, 이들 액포들은 융합에 의한 exocytosis로 원형질막 근처로 이동하여 원형질막과 융합한 다음, 세포벽 물질을 원형질막 바깥으로 방출하여 원형질막에 침적하였다. 전색소체는 많은 전분립을 함유하고 있었고, 미소관들은 원형질막 근처에서 막과 평형으로 배열하고 있었다. 배양된 원형질체의 표면에는 섬유소로 구성되어 있는 원섬유들이 서로 연결되어 있는 것이 관찰되었다.

• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.371-375
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• 1999

AL072 is a potent anti-Legionella antibiotic produced by Streptomyces strain AL91. The minimum inhibitory concentration (MIC) of AL072 against Legionella pneumophila was 0.2$\mu$g/ml. Bacterial growth was rapidly inhibited at the dose range between the MIC and 20 times of the MIC when the antibiotic was added at the mid-exponential phase. Ultrastructural changes in L. pneumophila were observed upon treatment with AL072. Under electron microscopical observation, the organisms treated with AL072 exhibited characteristic morphological changes in the cellular outer coat. Also irregular morphological changes, such as the formation of filamentous materials in the cytoplasm, an increase in the size and number of cytoplasmic vacuoles, the extruding of cytoplasmic contents, the formation of spheroplast and ghost cells, and blebbings in the cell wall were observed. Furthermore, immunoelectron microscopical observation of the group treated with the MIC showed that the immune complex attached mainly to the cell wall. The results of these experiments indicate that AL072, like the inhibitors of cell wall synthesis, act selectively on the cell wall of L. pneumophila.

• 한국건축시공학회지
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• 제8권6호
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• pp.123-129
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• 2008

The purpose of this study is to test performances of 14 types of root barrier materials by applying testing plant: and soils suitable for weather and natural features of Korea. For testing Plants, Plioblastus pygmaed Mitford A and Pyracantha angustifolia have been selected. For testing soil, mixture of pearlite and peat moss in 3:1 ratio Testing container has been fabricated with duplicated structure having inner and outer containers. And the outer container has 2 hinges on its side wall to allow opening and closing. Wet rock wool with 50mm in thickness has been inserted between inner and outer containers to allow root to penetrate through root barrier material and continue to grow. We planted 12 Plioblastus pygmaed Mitford A. and 4 Pyracantha angustifolia per one testing container. Three testing samples have been made for 1 type of root barrier material, which become a total 42 specimens. Planted testing samples have been installed within the greenhouse, which will be observed regularly for 2 years from now on. We started test from July 11, 2008 and had performed intermediate observations every month for initial 3 months. From the 3rd intermediate observation on Sept. 18, we confirmed that 6 types of roe barrier materials have penetrated roots. Even though two types of them have been generally used as root barrier materials for roof planting system, all of three testing samples have a lot of penetrated roots. This result proves that it is not reasonable to introduce testing methods of root barrier from Europe. USA or Japan.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 추계 학술논문 발표대회
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• pp.245-249
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• 2008

The purpose of this study is to test performances of 14 types of root barrier materials by applying testing plants and soils suitable for weather and natural features of Korea. For testing plants, Plioblastus pygmaed Mitford A. and Pyracantha angustifolia have been selected. For testing soil, mixture of pearlite and peat moss in 3:1 ratio(volume). Testing container has been fabricated with duplicated structure having inner and outer containers. And the outer container has 2 hinges on its side wall to allow opening and closing. Wet rock wool with 50mm in thickness has been inserted between inner and outer containers to allow root to penetrate through root barrier material and continue to grow. We planted 12 Plioblastus pygmaed Mitford A. and 4 Pyracantha angustifolia per one testing container. Three testing samples have been made for 1 type of root barrier material, which become a total 42 specimens. Planted testing samples have been installed within the greenhouse, which will be observed regularly for 2 years from now on. We started test from July 11, 2008 and had performed intermediate observations every month for initial 3 months. From the 3rd intermediate observation on Sept. 18, we confirmed that 6 types of root barrier materials have penetrated roots. Even though two types of them(EDPM Sheet, Polyethylene Sheet) have been generally used as root barrier materials for roof planting system, all of three testing samples have a lot of penetrated roots. This result proves that it is not reasonable to introduce testing methods of root barrier from Europe or Japan.

• Food Science and Biotechnology
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• 제14권3호
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• pp.410-412
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• 2005

Vibrio parahaemolyticus is a gram-negative bacterium which acts as a causative agent for food poisoning. Studies with respect to specific extracellular proteins of V. parahaemolyticus would be useful for the development of specific detection methods against V. parahaemolyticus. In our present study, outer membrane proteins (OMPs) of V. parahaemolyticus were obtained from insoluble traction of 1% sarkosyl treated-cell wall materials. SDS-PAGE analysis showed the presence of several conserved outer membrane proteins among five strains of V. parahaemolyticus, and three bands were identified as V. parahaemolyticus OMPs through MALDI-TOF analysis. Polyclonal antibodies enriched with anti-OmpU were obtained from immunized rabbits. The antibodies against these proteins may be useful for the development of detection methods for V. parahaemolyticus.

• 한국진공학회지
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• 제15권4호
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• pp.421-426
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• 2006

화학증착 시스템의 파이프내 발생하는 오염입자의 진단을 위하여 초음파 및 진동진단법을 각각 비교, 연구하였다. 초음파 진단의 경우 파이프 외벽에 초음파 센서를 부착하여 펄스를 가한 후 에코 분석을 통해 파이프내벽의 오염입자를 관찰하였고 진동 진단의 경우 파이프외벽에 부착된 진통발생기를 통해 파이프에 인위적인 진동을 발생시켜 여기에서 발생되는 주파수 차이를 분석, 파이프내의 오염입자 여부를 관찰하였다. 초음파 진단의 경우, 오염입자가 파이프 내벽에 부착되어 있을 때는 효과가 좋았으나 오염입자가 시간이 지남에 따라 건조되어 파이프 내벽에서 떨어져 나와 파이프 내벽과 오염입자사이에 틈새가 생길 경우 초음파 펄스는 이 공간을 통과하지 못하고 파이프 내벽에서 다시 반사되어 오염입자를 진단하지 못하는 경우가 발생하였다. 따라서 초음파 진단법으로는 진공장비의 오염입자 관찰에 재현성을 보여주지 못하는 것으로 확인되었다. 반면 진동진단법의 경우 위와 같이 일정시간이 지난 동일한 샘플의 경우에서도 오염입자에 의한 차이가 관찰되었다, 즉 파이프내 오염입자가 존재시 새 파이프에 비해 진동음이 저주파대로 떨어짐이 확인되어 추후 화학증착 시스템의 파이프내 오염입자 모니터링 연구에 가장 효과적인 방법으로 기대된다.