• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.462-470
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• 1995

The characteristics of spray-dried granules are important for dry pressing operation since they have great influences on die-filling, compaction ratio, and resulting green microstructure. An attempt was made to control granule morphology and the packing structure of fine Si3N4 particles in granules by adjusting suspension property. Mercury porosimetry was used to characterize the pore structures of both granules and green compacts. Finally, the effects of particle packing structure in granules and green microstructure on sintering behavior were investigated.

• The Bulletin of The Korean Astronomical Society
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• v.23
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• pp.17-17
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• 1998

• Korean Journal of Head & Neck Oncology
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• v.21 no.2
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• pp.170-173
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• 2005

Fine needle aspiration cytology (FNAC) of thyroid gland lesions has become a routine diagnostic method. And fine needle aspiration cytology is considered a safe, reliable and cost-effective means of selecting thyroid nodules with risk for malignancy. However, fine needle aspiration cytology of the thyroid may cause hemorrhage, infection, or trauma to adjacent structures. Hemorrhage sufficient to cause tracheal compression has not been reported. So we present a case of anterior neck hematoma causing tracheal compression after FNAC of the thyroid nodule.

• Journal of the Optical Society of Korea
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• v.19 no.5
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• pp.521-530
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• 2015

Active optics is a key technology for future large-aperture space telescopes. In the design of deformable mirrors for space applications, the design parameter trade-off between the number of regularly configured actuators and the correction capability is essential but rarely analyzed, due to the lack of design legacy. This paper presents a parametric module method for integrated modeling of deformable mirrors with regularly configured actuators. A full design parameter space is explored to evaluate the correction capability and the mass of deformable mirrors, using an autoconstructed finite-element parametric modeling method that utilizes manual finite-element meshing for complex structures. These results are used to provide design guidelines for deformable mirrors. The integrated modeling method presented here can be used for future applied optics projects.

• Journal of KIISE:Databases
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• v.28 no.4
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• pp.587-595
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• 2001

Precomputation and materialization of parts. commonly called views of a data cube is a common technique in data warehouses The view is defined as the result of a query which is defined through aggregate functions In this paper we introduce the concept of fine granule view. The fine granule view is the result of a query defined through aggregate functions and the range on each dimension, where the subdivision of each dimension is based on queries access patterns. For the representation and selection of fine granule views to materialize, we define the ANO-OR cube graph and AND-OR minimum cost graph. With these structures, we propose a fine granule view materialization method. And through experiments, we evaluate the performance of the proposed method.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1777-1783
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• 2014

Four $Cd^{II}$ MOFs, $[Cd_2({\mu}-succinate)_2(H_2O)_2]{\cdot}H_2O$ (1A), $[Cd_2({\mu}-succinate)_2({\mu}-4,4^{\prime}-bpy)_2]{\cdot}H_2O$ (1B), $[\{Cd_2({\mu}-succinate)_2\}({\mu}-bpa)_2\{Cd(H_2O)_2\}(NO_3)_2]{\cdot}H_2O$ (2), and $[Cd({\mu}-succinate)({\mu}-bpp)_2]{\cdot}2H_2O$ (3), with various bipyridyl ligands (4,4'-bipyridine (4,4'-bpy), 1,2-bis(4-pyridyl)ethane (bpa), and 1,3-bis(4-pyridyl)propane (bpp)) were prepared, and their structures were determined using X-ray crystallography. The structures and dimensionalities of $Cd^{II}$-(succinate) compounds varied depending on the auxiliary ligands. Heterogeneous catalytic activity for transesterification reactions, photoluminescence and the thermal stabilities of these compounds were also examined.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.558-564
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• 2013

A simple and effective method is introduced to synthesize a series of polystyrene-b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b-polystyrene (PSt-b-POEOMA-b-PSt) triblock copolymers. The structures of PSt-b-POEOMA-b-PSt copolymers were characterized by Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance ($^1H$ NMR) spectroscopy. The molecular weight and molecular weight distribution of the copolymer were measured by gel permeation chromatography (GPC). Furthermore, the self-assembling and drug-loaded behaviours of three different ratios of PSt-b-POEOMA-b-PSt were studied. These copolymers could readily self-assemble into micelles in aqueous solution. The vitamin E-loaded copolymer micelles were produced by the dialysis method. The micelle size and core-shell structure of the block copolymer micelles and the drug-loaded micelles were confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The thermal properties of the copolymer micelles before and after drug-loaded were investigated by different scanning calorimetry (DSC). The results show that the micelle size is slightly increased with increasing the content of hydrophobic segments and the micelles are still core-shell spherical structures after drug-loaded. Moreover, the glass transition temperature (Tg) of polystyrene is reduced after the drug loaded. The drug loading content (DLC) of the copolymer micelles is 70%-80% by ultraviolet (UV) photolithography analysis. These properties indicate the micelles self-assembled from PSt-b-POEOMA-b-PSt copolymers would have potential as carriers for the encapsulation of hydrophobic drugs.

• The Korean Journal of Cytopathology
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• v.16 no.1
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• pp.31-35
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• 2005

Eccrine acrospiroma is a rare adnexal tumor of the skin. When the clinical presentation is that of a breast lump, diagnosis can be difficult. Also, most of the cytopathologists are not familial with the cytologic features of this tumor and this is responsible for diagnostic pitfalls. We experienced a case of eccrine acrospiroma of the right breast in a 41-year-old female, misdiagnosed by fine needle aspiration cytology (FNAC). FNAC was characterized by tight clusters or sheets of small round cells, polygonal cells, and spindle cells and tubule like structures within clusters. Myoepithelial cells were not noted in the clusters. The diagnosis of eccrine acrospiroma was confirmed by histology.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.58-63
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• 1999

Almost all concrete structures have many inevitable cracks for various reasons such as drying shrinkage, heat liberation of cement, fatigues or repeating loads and movements. Conventionally, they are repaired with epoxy materials. The Epoxy resins used by repair materials are different from properties of the base concrete materials such as thermal and mechanical properties - thermal expansion coefficients, bending strength. And the epoxy resin cannot release the water inside the concrete structure and cause corrosion of the steel bars. In this study, before the experiment got launched, we had analyzed cement and slag. Then We blended the two grades of ultra fine cement using high blaine cement and slag. And the cement slurry was produced by water and suprplasticizer to each blended ultra fine cement in various conditions. The slurry produced by each conditions was evaluated with flow properties such as viscosity, dropping time, segregation and observation of dry surface after injection.

• Journal of Plant Biology
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• v.19 no.4
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• pp.100-106
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• 1976

The fine structure of the callus induced from epidermis of Panax ginseng leaves cultured on Murashige & Skoog medium plus kinetin 0.1mg/l, NAA 0.2mg/l and 2.4-D 0.5mg/l was observed. The cells composing callus tissue are mononucleus. Three types of cells were identified; cells with abundant cytoplasm, cells with relatively differentiated vacuoles and with numerous starch grains in the plastids and ones with highly differentiated vacuoles and with unsaturated lipid granules. Prolamellar body, plastid lamellae, plastid globules, stromacenter, fine tubules, crystal-containing body and DNA-like structures were observed in the stroma of the plastids. The chromoplasts were identified in some cells believed as the mother cells of secretory cells in secretory ducts. Curved or straight micro-fibrils of 100~150A in diameter were observed in the cytoplasm. And the characteristics of cell organelles and cell inclusions and the vacuole formation in callus tissues were discussed.