• Journal of the Korean Institute of Rural Architecture
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• v.16 no.3
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• pp.27-36
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• 2014

The purpose of this study is to provide necessary information for the establishment of remodeling range needed first to support the future remodeling of rural housing. For this, this study examined landscape characteristics of rural housing such as an outer wall, a roof, a fence, and a gate which are main elements of forming the landscape of a rural village and rural residents' perception for remodeling. The results were as follows. The subject rural housing mostly had a timber structure and a masonry structure. Common roof types were a hip-and-gable roof and a gable roof. Frequent materials were a panel, a tile, and slate and common colors were primary colors such as reddish brown, black, and gray. A fence made of cement blocks and finished by a white paint was often found. A closed gate with iron frames was common. A standup kitchen and a flush toilet inside the house were common. The family members of rural residents were mostly two including a farmer husband and his wife. Elderly people of sixty and over were the most common. For residential environment satisfaction, a half of respondents were not unsatisfied with residential environment mostly due to an old house. Most respondents who were not satisfied with residential environment had high perception for the need of remodeling. The most commonly asked remodeling part was a roof, followed by a toilet, and an outer wall, indicating that the need of exterior remodeling was higher than that of interior remodeling. For a remodeling method, a total improvement was preferred. Although some rural village housing was improved by support of the government, local governments, or social groups, there are still many old houses. As this co-existence of improved houses and old houses hinders the landscape of rural village, it is necessary to give a support. But rural residents' requests should be first actively reflected to establish a guideline of supporting rural house remodeling.

• Economic and Environmental Geology
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• v.27 no.2
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• pp.131-145
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• 1994

The Daehung and Pyeongan talc mines are located in the Yoogoo area, Chungcheongnam-Do. These deposits occur as the complex vein type in the ultramafic rocks which intruded Precambrian gneiss. The talc ore formed from sepentinitt: originated from ultramafic rocks but some of those from hornblende gneiss. The talcification processes were considered here on the basis of the mineral assemblages, paragenesis, and geochemistry. It appears that there are five processes in talcification ; serpentine$\rightarrow$talc, phlogopite$\rightarrow$chlorite$\rightarrow$talc, phlogopite$\rightarrow$talc, hornblende$\rightarrow$chlorite$\rightarrow$talc, and hornblende$\rightarrow$talc. Among them, the most dominant alteration path is serpentine to talc in these deposits. EPMA data suggest that there might be interstratified minerals were in between parent mineral and talc such as serpentine and talc, and phlogopite and talc. It can be found that tremolite exists in between the inner and outer most part of talcified serpentinite blocks coated with phlogopite. Some of tremolites has been altered to talc. The quartz veins and carbonate minerals were found in the talc ore zone. It indicates that the hydrothermal solution played an important role in talcification. The hydrothermal alteration occured after sepentinization. Ore zones can be divided into two zones; talc-serpentine zone preserving a pseudormorph of olivine (mesh texture) and talc-phlogopite zone showing talcification from phlogopite directly or through chlorite. It can be concluded that the formation of major talc ore body was due to talcification of serpentinite and phlogopite by hydrothermal solution. A nature of hydrothermal solution was relatively pure water at the beginning of serpentinization, and was getting richer in silica composition. There was a large amount influx of K and AI with hydrothermal solution in the later stage, and increased $P_{CO_{2}}$ also. It suggests that phlogopite formed in later stages as a secondary mineral. So, the major part of the talc ore body was formed from one parents rocks, serpentinite originated from ultramafic rocks, by hydrothermal solutions at several times.

• Imaging Science in Dentistry
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• v.50 no.2
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• pp.125-132
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• 2020

Purpose: The positions of the mandibular foramen (MnF) and the lingula affect the success rate of inferior alveolar nerve block. The objective of this study was to investigate aspects of the MnF and the lingula relevant for mandibular block anesthesia using cone-beam computed tomography (CBCT). Materials and Methods: Fifty CBCT scans were collected from a picture archiving and communications system. All scans were taken using an Alphard Vega 3030 (Asahi Roentgen Co. Ltd., Kyoto, Japan). Fifty-eight MnFs of 30 subjects were included in the study. The position of the MnF, the size of the MnF, the position of the lingula, the size of the lingula, and the shape of the lingula were measured and recorded. All data were statistically analyzed at a significance level of P<0.05. Results: The position of MnF was 0.1 mm and 0.8 mm below the occlusal plane in males and females, respectively. The horizontal position of the MnF was slightly anterior to the center of the ramus in males and in the center in females (P<0.05). The vertical position of the MnF was lower in females than in males(P<0.05). The MnF was an oval shape with a longer anteroposterior dimension. The height of the lingula was 9.3 mm in males and 8.2 mm in females. The nodular type was the most common shape of the lingula, followed by the triangular, truncated, and assimilated types. Conclusion: CBCT provided useful information about the MnF and lingula. This information could improve the success rate of mandibular blocks.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8161-8169
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• 2014

Background: Cancer stem cells (CSC) are populations of cells responsible for tumor initiation, progression and therapeutic resistance in many cancers. In the present study, we aimed to investigate the expression pattern and clinical significance of two CSC markers, CD133 and Nestin, in a series of skin tumors. Materials and Methods: One hundred and thirteen paraffin blocks from skin cancers including 16 (14%) cases of melanoma, 37 (33%) of squamous cell cancer (SCC) and 60 (53%) of basal cell cancer (BCC) were collected and assembled in a tissue microarray (TMA). The samples were immunohistochemically examined for the expression of CD133 and Nestin. Expression of these markers was also correlated with clinicopathological parameters. Results: A significant difference was observed in the expression of CD133 and Nestin in melanomas, SCC and BCC (p value=0.001). Furthermore, the level of expression was significantly higher in the melanomas compared to the SCC and BCC tumors. Expression of CD133 in the melanoma was significantly associated with increased tumor invasiveness (p value=0.05), a higher rate of metastasis (p value=0.04) and the presence of ulceration (p value=0.02). Increased expression of Nestin was observed in metastatic melanoma (p value=0.04), while no statistically significant correlation was found with other clinicopathological parameters including Breslow thickness, Clark level and ulceration. Conclusions: Elevated expression levels of CD133 and Nestin in the melanomas are associated with advanced disease, with more aggressive and metastatic skin tumors. Therefore, these markers could be potential therapeutic targets for malignant tumors of the skin.

• Journal of the Korea Concrete Institute
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• v.16 no.6 s.84
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• pp.875-881
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• 2004

The quality of recycled aggregate is affected by original concrete strength and the manufacturing process of recycled aggregates. In this study, the porosity of old and new mortar, and the compressive strength of concrete were investigated to examine the influence of recycled aggregate on the concrete. Six kinds of recycled coarse aggregates were produced from concrete blocks of differing strength levels (A:60. 1MPa, B:41.7MPa, C:25.5MPa). Original concrete strength and the bond mortar of recycled aggregate influences the pore structures of both old and new mortar. The pore size distribution of old mortar was found to be greatly affected by age, and the reduction of the porosity of bond mortar on low strength recycled aggregate increased at a greater rate than that of bond mortar on high strength recycled aggregate. The pore size distribution of new mortar in recycled aggregate concrete changed in comparison with that of new mortar in virgin aggregate concrete. The total porosity of new mortar using B level recycled aggregates was smaller than that of new mortar with A, and C level recycled aggregates. Moreover, the compressive strength of recycled aggregate concrete was found to have been affected by original concrete strength. The compressive strength of concrete only changed slightly in the porosity of new mortar over $15\%$, but increased rapidly in the porosity of new mortar fewer than $15\%$.

• Journal of the Korean Geosynthetics Society
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• v.14 no.2
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• pp.35-44
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• 2015

The resilient modulus model of EPS geofoam to be used for a flexible pavement design was developed. In this study, the model was applied to design the flexible pavement and to predict the magnitude of the deformation of EPS geofoam blocks as a subgrade in the flexible pavement structure by using the resilient modulus model of EPS geofoam (RMEG) program. The RMEG program presented how much the EPS geofoam subgrade settled over the designed duration and the AASHTO flexible pavement design equation with the resilient modulus of EPS geofoam noted that how long the flexible pavement endured under traffic loads with 70% reliability for the estimated duration with less than 5mm vertical deformation during 20.6 years without the significant pavement distress as a substitute material for the natural soils.

• Journal of Technologic Dentistry
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• v.35 no.1
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• pp.19-27
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• 2013

Purpose: The aim of this research was to evaluate the shear bond strength of different zirconia veneering ceramics with and without liner glass materials to yttria partially-stabilized tetragonal zirconia polycrystalline(Y-TZP). Methods: Five co mmercial zirconia veneering ceramics were used in this study, E-Max(EM), Creation ZI(CR), Cercon ceram kiss(CE), Triceram(TR) and Zirkonzahn ICE(ZI). All samples were prepared according to manufacturer's instructions. Experimental industrially manufactured Y-TZP ceramic blocks(diameter: 2.7 mm; height: 13.5 mm) were used in this study. Shear bond strength between zirconia ceramic coping and zirconia veneering ceramics were evaluated by the push-shear bond test. The fracture load data were analyzed using ANOVA and Scheffe's test(${\alpha}$=0.05). The fractured surfaces of zirconia core ceraimc and zirconia veneering ceramics were observed using a scanning electron microscope(SEM). Results: The mean shear bond strengths ranged from 20 MPa ($20.12{\pm}6.34$ MPa) to 66.6 MPa ($66.62{\pm}10.01$ MPa). The Triceram(TRG) showed the highest value and Creation ZI(CR) showed the lowest value. In all groups, Zirconia liner and glass material groups was significantly higher shear bond strength than without liner(P<0.05), with the exception of Cercon ceram kiss(CE)groups. Conclusion: Zirconia bonding materials may have the advantage of improved bond strength between zirconia ceramic core and veneering ceramics.

• Advances in nano research
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• v.5 no.3
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• pp.215-230
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• 2017

The development of hybrid systems comprising nanoparticles and polymers is an opening pathway for engineering nanocomposites exhibiting outstanding mechanical, optical, electrical, and magnetic properties. Among inorganic counterpart, iron oxide nanoparticles (IONP) exhibit high magnetization, controllable surface chemistry, spintronic properties, and biological compatibility. These characteristics enable them as a platform for biomedical applications and building blocks for bottom-up approaches, such as the layer-by-layer (LbL). In this regard, the present study is addressed to investigate IONP synthesised through co-precipitation route (average diameter around 7 nm), with either positive or negative surface charges, LbL assembled with sodium sulfonated polystyrene (PSS) or polyaniline (PANI). The surface and internal morphologies, and electrochemical properties of these nanocomposites were probed with atomic force microscopy, UV-vis and Raman spectroscopy, scanning electron microscopy, cross-sectional transmission electron microscopy, and electrochemical measurements. The nanocomposites display a globular morphology with IONP densely packed while surface dressed by polyelectrolytes. The investigation of the effect of thermal annealing (300 up to $600^{\circ}C$) on the oxidation process of IONP assembled with PSS was performed using Raman spectroscopy. Our findings showed that PSS protects IONP from oxidation/phase transformation to hematite up to $400^{\circ}C$. The electrochemical performance of nanocomposite comprising IONP and PANI were investigated in $0.5mol{\times}L^{-1}$ $Na_2SO_4$ electrolyte solution by cyclic voltammetry and chronopotentiometry. Our findings indicate this structure as promising candidate for potential application as electrodes for supercapacitors.

• Journal of the Korea Computer Graphics Society
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• v.15 no.3
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• pp.11-18
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• 2009

In this paper, we introduce a novel method to extend the JPEG standard, which is the most widely used for lossy image compression, in order to improve compression ratio. To employ two of the most successful methodologies for the data compression: differential coding and quantization simultaneously, we propose a line-based approach. For each line in a block, we apply one-dimensional discrete cosine transformation to the increments instead of the pixel values. Those values are quantized and entropy-coded similarly to the JPEG standard. To further increase compression ratio, the proposed method is plugged into the JPEG standard to form a new compression method, in which the proposed method are applied to only selected JPEG blocks. In our experiment, we found that the proposed method outperform the JPEG standard when the qualities of the coded images are set to be high. We believe the proposed method can be simply plugged into the standard to improve its compression ratio for higher quality images.

• Journal of the Korea Concrete Institute
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• v.21 no.1
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• pp.47-53
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• 2009

12 concrete blocks, on which hybrid fibrous sheets (carbon fiber and glass fiber) had been bonded, were subjected to tensile load in order to estimate properties of the bonded interface. the sheet length was varied by 100mm, 200mm and 400mm. It was found that more than 150mm bond length is required to achieve the maximum bearing capacity of the interface. In this study, maximum bond stress $\tau_{F,max}$, ultimate slip $S_{FU}$ of the interface were estimated $\tau_{F,max}$=3.0MPa and $S_{FU}$= 0.175mm, respectively.