• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1663-1670
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• 2006

Single crystal Fe thin films were grown directly onto n-Si(111) substrates by pulsed electrodeposition. Cyclic Voltammogram(CV) indicated that the $Fe^{2+}/n-Si(111)$ interface shows a good diode behavior by forming a Schottky barrier. From Mott-Schottky (MS) relation, it is found that the flat-band potential of n-Si(111) substrate and equilibrium redox potential of $Fet^{2+}$ ions are -0.526V and -0.316V, respectively. The nucleation and growth kinetics at the initial reaction stages of Fe/n-Si(111) substraste was studied by current transients. Current transients measurements have indicated that the deposition process starts via instantaneous nucleation and 3D diffusion limited growth. After the more deposition, the deposition flux of Fe ions was saturated with increase of deposition time. from the as-deposited sample obtained using the potential pulse of 1.4V and 300Hz, it is found that Fe nuclei grows to three dimensional(3D) islands with the average size of about 100nm in early deposition stages. As the deposition time increases, the sizes of Fe nuclei increases progressively and by a coalescence of the nuclei, a continuous Fe films grow on the Si surface. In this case, the Fe films show a highly oriented columnar structure and x-ray diffraction patterns reveal that the phase ${\alpha}-Fe$ grows on the n-Si(111) substrates.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.1
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• pp.19-24
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• 2012

Barium zirconate exhibits good thermo-chemical stability and proton conduction at high temperatures, but shows poor electron conductivity. Therefore, for high efficiency of hydrogen separation, a very thin and dense Pd-Barium zirconate membrane has to be coated on a porous substrate. A thin and dense Pd-Barium zirconate membrane was successfully synthesized on a porous substrate by means of dual sputtering method. The structural and chemical features of the $BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ membranes sputtered at $300^{\circ}C$ and $400^{\circ}C$ were investigated by X-ray diffractometry, and it was found that a well-crystallized membrane, Pm-3m space group of $BaZrO_3$, was synthesized. The surface and cross-sectional morphologies of membrane were assessed by SEM (scanning electron microscopy) and TEM(transmission electron microscopy) of the surface and of cross sections. The cross sectional observation of Pd-$BaZr_{0.85}Y_{0.15}O_{3-{\delta}}$ membrane by dual sputtering shows that the coating is quite dense with columnar structure.

• Journal of Navigation and Port Research
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• v.44 no.4
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• pp.305-311
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• 2020

Rising sea levels along the coast from global warming causes the increase of wave energy along the coast. This rise in sea levels results in relatively deep water levels, which would incur the loss of sand that had not occurred in the past from erosion in coastal areas. Generally, it has been challenging to protect against coastal erosion, and the slope, cross-sectional shape, and materials are selected for the site conditions depending on the change in external forces. However, the application of counter measures based on insufficient understanding of the phenomenon is causing various damage, indicating the need for technological development and converging technologies to improve credibility. In this study, we developed eco-friendly permeable biopolymer concrete blocks to control the coastal erosion by using the Bio-Coast, an effective porous structure that mitigates the destructive erosion caused by the rising sea levels. The hexagonal design of Bio-Coast was derived from the honeycomb, columnar joints, and clover, which are durable and stable structures in nature, and the design was changed to apply bumps on the Bio-Coast filling in the form of a clover to reduce wave overtopping and run-up. Applying the field condition of beaches on the east coast of Korea, the block weight and size were decided and the prototype blocks were manufactured and are ready for field placement. In particular, it is intended to protect coastal areas from destructive erosion by natural and artificial external forces, and to extend the design to river,s lakes, and natural walking trails, to improve the efficiency of quality control and process control through the use of blocks.

• Journal of the Korean earth science society
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• v.26 no.1
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• pp.78-92
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• 2005

Petrographical and petrochemical analyses for late Miocene basalts in Goseong-gun area. Gangwon province, were carried out to interpret the characteristics and the origin of magma. The basaltic rocks occurred as plug-dome in the summit of several small mountain and developed columnar jointing with pyroxene-megacryst bearing porphyritic texture. And the basalt contains xenoliths of biotite granite (basement rocks), gabbro (lower crustal origin) and Iherzolite(upper mantle origin). The basalts belong to the alkaline basalt field in TAS diagram and partly belong to picrobasalt and trachybasalt field. On the tectonomagmatic discrimination diagram f3r basalt in the Goseong-gun area. they fall into the fields for the within plate and oceanic island basalt. The characteristics of trace elements and REEs shows that primary magma for the basalt magma would have been derived from partial melting of garnet-peridotite mantle. This late Miocene basalt volcanism is related to the hot spot within the palte.

• Journal of the Korean earth science society
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• v.34 no.2
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• pp.109-119
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• 2013

Duibaejae basalts from Goseong, Gangwon-do, are divided into the lower basalt and the upper basalt depending on the properties, such as occurrence, mineral compositions, and major and trace compositions of the basalts. The lower basalts have characteristics of agglomerate rocks as well as contain, crustal and mantle xenoliths, and olivine, pyroxene, and plagioclase xenocrysts. The upper basalts with columnar joints contain relatively more mantle xenolith and olivine xenocryst than the lower basalts. The major and trace element compositions suggest that the composition of the upper basalts is close to primary magma composition. Enrichment and depletion patterns of the trace and the rare-earth elements of the lower basalts are similar to those of the upper basalts, whereas the lower basalts are more LREE enriched than the upper basalts. The source magmas of the lower and upper basalts from Duibaejae volcanic edifice were generated from about 0.8-1.2% and 3.7-4.0% batch melting of garnet peridotite, respectively. The abundance of granite xenolith, and plagioclase and quartz xenocrysts with reaction rim indicates that the lower basalts, compared with upper basalts, might have been assimilated with the crustal materials during ascending to surface.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.139-144
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• 1984

A case of foregut cyst communicated with esophagus and lined by bronchial mucosa is reviewed and its embryologic base of maldevelopment is discussed. It is not always easy to distinguish between digestive and respiratory cyst in mediastinum. There is whole range of intermediate between a cyst with ciliated and one with squamous or columnar mucosa. Origin of this dysembryoplasia is difficult to determine when one consider that the esophagus is covered with ciliated epithelium until the eleventh week of fetal life and that ciliated growth are found on its wall until the sixth month of the fetal life. And we concluded, general agreement is that cysts which have gastric epithelium in whole or in part, represent a distinct type and should be classified as (gastro) enteric cyst, mediastinal cyst containing cartilage were considered definitely as respiratory(bronchial or bronchogenic) cyst.

• The Korean Journal of Cytopathology
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• v.10 no.1
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• pp.27-34
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• 1999

Benign and malignant papillary neoplasms of the breast may be difficult to distinguish in both cytologic and histologic preparations. To define the cytologic features of benign and malignant papillary lesions, we retrospectively reviewed 18 cases of fine needle aspirates from histologically confirmed cases of papilloma or papillary carcinoma of the breast. This study included 3 intraductal papillary carcinomas, 3 invasive papillary carcinomas, and 12 intraductal papillomas. Ail cases were evaluated for presence or absence of papillary fragments, bloody background, apocrine metaplasia, macrophages, and degree of cellularity, atypia, and single isolated columnar epithelial cells. Papillary fragments were present in all cases. The background of the smear was bloody in all 6 carcinomas, but in only 7 out of 12 papillomas. Markedly increased cellularity was present in 4 carcinomas(67%) and 7 papillomas(58%). Single cells were present in 5 carcinomas(83%) and 8 papillomas(67%). The majority of papillomas and papillary carcinomas had mild to moderate atypia, and severe atypia was noted in one case of intraductal papillary carcinoma and one case of invasive papillary carcinoma. Apocrine metaplasia was absent in all cases of papillary carcinomas, but present in 8 papillomas(57%). Macrophages were noted in 4 carcinomas and were present in all cases of papillomas. The constellation of severe atypia, bloody background, absence of apocrine metaplasia and/or macrophages were features to favor carcinoma. Malignant lesions tended to show higher cellularity and more single isolated cells. The cytologic features mentioned above would be helpful to distinguish benign from malignant papillary lesions of the breast. However, because of overlapping of cytologic features, surgical excision should be warranted in all cases on papillary lesions of the breast to further characterize the tumor.

• Development and Reproduction
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• v.2 no.1
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• pp.45-52
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• 1998

An enhncer detector line(EDL) having P[1ArB] insertion in X chromosome with expression of reporter gene (lacZ) in the polar cells and border cell of egg chamber was established and used to monitor the differentiation and migration of border cells during the oogenesis of Drosophila. differentiation of border cell from the anterior polar follicle cells was evident in stage-9 egg chamber of EDL149 which was characterized by migration of columnar follicle cells toward posterior of egg chamber surrounding the oocyte. Migration of border cells was observed in the stage-9 and -10 egg chambers. \beta -galactosidase activities were rapidly increased during the first 4 days after eclosion, and it coincided with the timing of border cell differentiation in the ovary during adult life. Homozygote of EDL149 showed some retardation of border cell migration , resulting absence of migration of some border cells in the anterior part of egg chamber or delayed migration of some border cells in the stage-10 egg chamber. These results suggest that the P[1ArB] of EDL149 is inserted at the locus of the structural gene required for the border cell migration. In addition to the expression in egg chambers, lacZ expression was also detected in the meiotic germ cells of testis and antenna, suggesting the possible requirement of the trapped gene function in these organ. this EDL and enhancer trapped gene might be useful for the study of developmentally regulated cell migration.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.212-215
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• 1998

Pulmonary mucinous cystic tumor of borderline malignancy is very rare and distinguished from bronchogenic cyst or adenocarcinoma of bronchoalveolar type. We present the case of a 63-year-old woman with a right lower lobe mass, found by chest radiographs. The preoperative diagnosis was made as bronchoalveolar cancer by percutaneous needle aspiration of mass. Right lower lobectomy and lymph node dissections were performed. The lobectomy specimen contained variable sized multilocular cystic mucous masses, filled with mucus. Microscopically, the cystic masses are lined with tall columnar mucinous epithelium but some area contains focal cellular atypism and bronchoalveolar cancer like foci. This foci are lack of cellular atypism consistent with bronchoalveolar cancer cell. After lobectomy the patient has remained free from recurrence and distant metastasis for following 12 months period. Pulmonary mucinous cystic tumor of borderline malignancy appears to have a favorable prognosis and should be distinguished from other lung neoplasms.

• Korean Journal of Ichthyology
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• v.19 no.2
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• pp.112-119
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• 2007

A histological study on development and transformation of the oocyte' follicle cell for Korean four sillurid fishes, Liobagrus obesus, L. mediadiposalis, Pseudobagrus koreanus, and P. brevicorpus was performed by light and electron microscopes. The follicular layer surrounding the oocyte consisted of an outer theca cell and an inner follicle cell (granulosa cell). The follicle cells of the oocyte were flatten cells at early oocyte but during vitellogenesis they were transformed it to a single layer of cuboidal cell, then to a single columnar cell layer, and finally to a layer covered with a substance secreted by themselves. Although the development and transformation of the follicle cells was similar to four species, the secreted materials, called an adhesive membrane, were divided into two types in its appearance and nature. Firstly, a jelly coat-like type was found in L. obesus and L. mediadiposalis, which they are presumed to be polysaccharides and mucoproteins in its nature and secondly, a granular type in P. koreanus and P. brevicopus, being mucoprotein. A zona radiata with about $0.6{\sim}3.1{\mu}m$ thin was present below the adhesive material secreted by the transformed-follicle cell's activity. The zona radiata was composed of two layers, a thin externa and a thick interna.