• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.481-488
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• 2000

The mechanism of soil-geotextile system has been studied among researchers since the application of geotextile as a replacement of graded granular filters is rapidly growing. The interaction of soils with geotextile is rather complicated so that its design criteria are mostly based on empiricism. Hence, it is essential to study the characteristics of fine particles transport into geotextile induced by the groundwater flow In this study, the permeability reduction in the soil-filter system due to clogging phenomenon is evaluated. An extensive research program is performed using two typical weathered residual soils which are sampled at Shinnae-dong and Poi-dong area in Seoul. Two separate simulation tests with weathered residual soil are peformed: the one is the filtration test(cross-plane flow test): and the other is the drainage test(in-plane flow test). Needle punched non-woven geotextiles are selected since it is often used as a drainage material in the field. The compatibility of the soil-filter system is investigated with emphasis on the clogging phenomenon. The hydraulic behaviour of the soil-filter system is evaluated by changing several testing conditions.

• The Korean Journal of Cytopathology
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• v.12 no.2
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• pp.127-130
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• 2001

Solid papillary carcinoma of the breast is a distinctive form of intraductal papillary carcinoma frequently associated with both mucinous carcinoma and infiltrating ductal carcinoma, not otherwise specific. To our knowledge, this case is the first description of the cytologic aspects of solid papillary carcinoma of the breast in the Korean literature. We experienced a case of solid papillary carcinoma of the right breast diagnosed by fine needle aspiration cytology(FNAC) in a 70-year-old female. FNAC from the right breast showed high cellularity consisting of mostly tight clusters of tumor cells and a few scattered tumor cells. The nuclei were monotonously round to oval in shape with inconspicuous nucleoli. The cytoplasm was abundant and finely granular. Scant amount of mucinous material was present on the background. The diagnosis was confirmed histologically and immunohistochemically.

• The Korean Journal of Cytopathology
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• v.12 no.2
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• pp.131-134
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• 2001

Cytologic features of conventional chordoma have been described and most reports emphasize the presence of large cells with numerous well defined cytoplasmic vacuoles or physaliferous cells. We report fine needle aspiration cytologlc (FNAC) findings of a case of chordoma without physaliferous cells. The smear was cellular and composed of large cohesive clusters or individually scattered cells in mucinous background. The round or cuboidal cells had centrally located nuclei with fine granular chromatin, inconspicuous nucleoli, and occasional vacuolated cytoplasm. Mild to moderate pleomorphism was noted. Physaliferous cells are extremely helpful when present in cytologic material, but they are not necessary for diagnosis. Thus clinical history, roentgenographic appearance, and exact location of the lesion are required for the successful Interpretation of presacral aspirates together with cytologic findings.

• The Korean Journal of Cytopathology
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• v.12 no.1
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• pp.45-48
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• 2001

Acinic cell carcinoma(ACC) is the third common malignancy in major salivary gland. Fine needle aspiration cytology is a useful tool for the diagnosis of salivary gland lesions. However, some low grade malignancies, such as ACC and mucoepidermoid carcinoma show relatively high false negative rate, mainly due to deceptively benign cytomorphologic appearance. We experienced a papillary-cystic variant of ACC, having different cytopathologic features compared with those of classic ACC. Our case showed monolayered sheets and papillary clusters without any acinic structures or naked nuclei of the tumor cells. Foamy proteinaceous material was seen in the background. The tumor cells had a large amount of granular cytoplasm and eccentric nuclei. Many vacuolated or clear cells were also noted.

• Steel and Composite Structures
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• v.19 no.4
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• pp.939-952
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• 2015

In this paper, brake pad performance of two organic matrix composites namely, Sample 1 (contains no brass filler) and Sample 2 (contains 1.5% brass filler), is studied based on tribological and squeal noise behavior. In the first stage, a pin-on-disc tribometer is used to evaluate the frictional behavior of the two pads. On the following stage, these pads are tested on squeal noise occurrence using a drag-type brake dynamometer. From the two type of tests, the results show that; (i) brass fillers play a dual role; firstly as reinforcing element of the brake pad providing primary contact sites, and secondly as solid lubricant by contributing to the formation of a layer of granular material providing velocity accommodation between the pad and the disc; (ii) brass fillers contribute to friction force stabilization and smooth sliding behavior; (iii) the presence of small weight quantity of brass filler strongly contributes to squeal occurrences; (iv) there is close correlation between pin-on-disc tribometer and brake dynamometer tests in terms of tribological aspect.

• Journal of Sasang Constitutional Medicine
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• v.14 no.1
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• pp.100-111
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• 2002

1. The Purpose of study An experimental study has done to examine the effect of defense on gastric mucosal damage of Jowesungcheong-tang. 2. The Material and Method of study Mice had intragastric injected with JST extract before indome thacin treatment which induces hemorrh age erosion artificially. General morphology, infiltrative cell in mucosa, the distribution of UEA-I, COX-1, MAC-1. ICAM, and Apoptotic cell were objected (Ahhreviation) JST :Jowesungcheong-tang, UEA-I : ulex europaeus agglutinin-I, COX-1: cyclooxyhenase-1, ICAM : intercellular adhesion molecule-1, GPE : Gastropathy elicitated mice 3. The results and Conclusions of study 1) The degree of hemorrhage erosion in GPE-group had increased conspicuously in gastric gland proper. JST -group were the same as normal 2) The noticeable increase of granular lecocytes and lymphocytes in GEP-group were seen, but in JST group, the configuration is decreased 3) The decrease of UEA-I positive reacted cells, COX-1, surface epithelial cells and the increase of MAC-l positive cells, ICAM-l positive cells had shown in GPE-group, but in JST-group UEA-I positive cells, COX-1 surface epithelial cells were in creased and MAC-1 positive cells, ICAM-l positive cells were decreased than GPE-group. 4) A number of apoptotic cells were distributed in hemorrhage erosion. The remarkable decrease of apoptotic cells were shown in JST-group.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.607-614
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• 2010

Shear behavior of granular soils largely affects the safety and stability of underground and earth structures. This study presents the characteristics of shear zone in a direct shear test using shear wave and electrical resistivity measurements. An innovative direct shear box made of transparent acrylic material has been developed to prevent direct electric current. Bender elements and electrical resistivity probe are embedded in the wall of direct shear box to estimate the shear wave velocities and the electrical resistivity at the shear and non-shear zones. Experimental results show that the void ratio and shear wave velocity at shear zone increase during shearing while the values remain constant at non-shear zone. The results demonstrate correlation among the contact force, small strain shear modulus, and void ratio at shear zone. This study suggests that the application of the modified direct shear box including shear wave and electrical resistivity measurements may become an effective tool for analyzing soil behavior at shear zone.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.115-127
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• 1999

The charged clusters or particles, which contain hundreds to thousands of atoms or even more, are suggested to form in the gas phase in the thin film processes such as CVD, thermal evaporation, laser ablation, and flame deposition. All of these processes are also used in the gas phase synthesis of the nanoparticles. Ion-induced or photo-induced nucleation is the main mechanism for the formation of these nanoclusters or nanoparticles inthe gas phase. Charged clusters can make a dense film because of its self-organizing characteristics while neutral ones make a porous skeletal structure because of its Brownian coagulation. The charged cluster model can successfully explain the unusual phenomenon of simultaneous deposition and etching taking place in diamond and silicon CVD processes. It also provides a new interpretation on the selective deposition on a conducting material in the CVDd process. The epitaxial sticking of the charged clusters on the growing surface is gettign difficult as the cluster size increases, resulting in the nanostructure such as cauliflowr or granular structures.

• Journal of the Korean Ceramic Society
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• v.14 no.3
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• pp.163-168
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• 1977

As a wet chemical drying process "hot petroleum drying method" was applied and developed for preparing uniformly fine oxide powder with high purity and sinterreactivity. Using this method solution of sulfates was dried in hot petroleum bath (~17$0^{\circ}C$) to sulfate powder from which corresponding mullite doped by Fe3+ ion was formed. Particle size, shape, decomposition by heat, and phase identification of sulfate andoxide powders determined by DTA, TGA, X-ray diffraction, analysis and electron microscopy: sulfate powder prepared by this drying method is an intimate mixture of the amorphous form of uniformly and finely distributed spherical particles (0.05-0.1$\mu$). Mullitization with the sulfate powder occurs at 110$0^{\circ}C$ in air. The morphology of mullite particle made by firing the sulfate powder at 135$0^{\circ}C$ in oxygen atmosphere is granular of 0.1-0.3$\mu$ in size. This drying process proved to be a very effective method for preparing fine, homogeneous, and highly sinterreactive multicomponent oxide powder without conventional ceramic process of mixing, milling, and granulating. This process can be also applied for preparing electronic ceramic materials which are requisite for high purity and homogeneity.mogeneity.

• Geomechanics and Engineering
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• v.4 no.3
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• pp.191-208
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• 2012

Due to rapid industrialisation, large scale infrastructure development is taking place worldwide. This includes railways, high speed highways, elevated roads etc. To meet the demands of society and industry, many innovative techniques and materials are being developed. In developed nations like USA, Japan etc. for railways applications, new material like geocells, geogrids are being used successfully to enable fast movement of vehicles. The present research work was aimed to develop design methodologies for improvement of grounds subjected to cyclic loads caused by moving vehicles on roads, rail tracks etc. Deformation behavior of ballast under static and cyclic load tests was studied based on square footing test. The paper presents a study of the effect of geo-synthetic reinforcement on the (cumulative) plastic settlement, of point loaded square footing on a thick layer of granular base overlying different compressible bases. The research findings showed that inclusion of geo-synthetics significantly improves the performance of ballasted tracks and reduces the foundation area. If the area is kept same, higher speed trains can be allowed to pass through the same track with insertion of geosynthetics. Similarly, area of machine foundation may also be reduced where geosynthetics is provided in foundation. The model tests results have been validated by numerical modeling, using $FLAC^{3D}$.