• Journal of the Korea Institute of Building Construction
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• v.18 no.2
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• pp.109-115
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• 2018

Since the current method of SCW cement milk pouring method uses one to one ratio of cement milk with OPC, there are some problems such as drying shrinkage, increased cost, difficulty of controlling mix proportions for various conditions of applied soil, and precipitation of $Cr^{6+}$ due to the excessively used cement. Specifically, in aspect of sustainability issues of cement manufacturing, the consumption of cement should be reduced. Hence, in this research, as a replacement of cement for SCW method, blast furnace slag with sulfate or alkali as a stimulant, and expansive admixture were used. By using blast furnace slag as a hardening composite of SCW, there are many advantages such as free controllable mix proportions, rapid setting time with less mud occurrence, less cost with less energy for mixing, constant strength development, and less precipitation of $Cr^{6+}$. Regarding the alternative composites for SCW, in this research, durability and chloride resistance were evaluated.

• Journal of the Korean Geosynthetics Society
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• v.17 no.1
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• pp.33-43
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• 2018

Two-row Overlap Pile wall is a novel retaining wall system with high flexural rigidity and waterproofing for deep excavation support currently being developed in Korea. The Two-row Overlap Pile wall is constructed by making an overlap between consecutive four-axis (or two-axis) auger piles which themselves are overlapped and arranged in zigzag manner. In this study, the flexural rigidity of the Two-row Overlap Pile wall, including the effect of cross-sectional shape, was examined using both theoretical and numerical approaches. The results of investigation suggested that the Two-row Overlap Pile wall formed with two-row piles exhibit greatly higher flexural rigidity than conventional one-row pile walls such as Cast in place pile (CIP) and Secant pile wall (SPW), whereas the effect of overlap length between piles on the flexural rigidity is relatively minimal.

• Imaging Science in Dentistry
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• v.32 no.1
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• pp.19-25
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• 2002

Purpose: To evaluate the degree of accuracy of DentaScan reformatted images of the maxillary sinus and periapical, periodontal lesions and to clarify the usefulness of the reconstructed 3-dimensional images to the dental clinical aspects. Materials and Methods: 33 sides of maxillae of the hemi-sectioned Korean heads were used in this study. Periapical radiographs, computed tomography and DentaScan reformatted cross-sectional images were taken for the radiographic evaluation of the peiapical and peiodontal lesions of the maxillary teeth and inferior wall of maxillary sinus. Results : Compared the degree of accuracy and findings of dental and periapical pathoses on the intraoral radiographs and DentaScan reformatted images with the cross-sectioned specimens, the DentaScan reformatted cross-sectional images were more accurate and more effective than the intraoral radiography with a viewpoint of the detection of dental and periapical pathoses. Conclusion: Comparing the lesions of specimens with intraoral radiographies and DentaScan reformatted images, the dental and periodontal pathoses and topographical structures were more clearly observed in the DentaScan reformatted images, providing the possibility of more applications of reformatted images to clinical dentistry.

• Journal of Korean Society of Forest Science
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• v.81 no.4
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• pp.357-362
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• 1992

To understand water flow path in the cells of Robinia pseudoacacia and Pyrus ussuriensis and obtain color wood from them, this experiment was performed by penetrating 0.5% acidic fuchsin and 0.5% fast green solution into the living wood of them. A comparison was made of the wood structure and water flow path from Robinia pseudoacacia containing the ring-porous wood with tyloses, and Pyrus ussuriensis including solitary diffuse-porous wood with distinct fiber pits. The dye penetrated into vessel elements in the early wood of two growth rings from bark in Robinia pseudoacacia, but permeated all xylem in fonts ussuriensis. In Robinia pseudoacacia, the vessels of heart wood and intermediate wood were not stained because of tyloses.

• Composites Research
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• v.17 no.1
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• pp.29-37
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• 2004

Honeycomb sandwich composite(HSC) structures have been widely used in aircraft and military industry owing to their light weight and high stiffness. Mechanical properties of honeycomb core materials are needed for accurate analysis of the sandwich composites. In this study. theoretical formula for effective elastic modulus and Poisson's ratio of honeycomb core materials was established using an energy method considering the bending, axial and shear deformations of honeycomb core walls. Finite-element analysis results obtained by using commercial FEA code, ABAQUS 6.3 were comparable to the theoretical ones. In addition, we performed tensile test of HSC plates and analyzed deformation behaviors and interlaminar stresses through its FEA simulation. An increased shear stress along the interface between surface and honeycomb core layers was shown to be the main reason for interfacial delamination in HSC plate under tensile loading.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.421-429
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• 2020

Purpose: The purpose of this study is to present step-by-step countermeasures to prevent fires in sandwich panel warehouses and to enhance on-site fire response capabilities. Method: Interviews of firefighters related to fire sites, advice from fire experts, and experiments on protection performance were conducted to draw up measures for each element to strengthen on-site response capabilities. Result: The fire safety management checklist for warehouse fire safety managers and the installation standards for wall protection of sandwich panel warehouses are presented. In addition, Standard Operational Procedures(SOP) for fire application of sandwich panel warehouses were established for firefighters on-site. Conclusion: Through this study, step-by-step fire safety measures were established for preventing, protecting and suppressing fires in sandwich panel warehouses.

• Archives of design research
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• v.17 no.2
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• pp.261-268
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• 2004

The Colonial House is one of the most popular styles in America. The purpose of this study is to closely examine this style based on interior features classified by patterns and elements during America's colonial period. Results of this study show that the interior style of the Colonial House was, at first, similar to Europe style. It was then integrated into the Georgian style of England and affected by Palladio as time passed. The interior style of the American Colonial House was based on rationality and practicality in concern with American weather and regions rather than imitation. The side of the roof was clapboard and the windows arranged with symmetry and rules around the entrance hall. It was generally Palladian style and was decorated with classical details. Timber frame of the interior was based on log cabins that appeared early in the American immigration. Furniture styles such as Jacobian, Queen Ann and Chippendale were matched with unique wood-oriented details and folkways like Chest, Rush Chair and Windsor Chair The house was also decorated with pictures, mirrors and ornaments, etc.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.40-46
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• 2015

Microcapsules containing the suspension of conducting materials such as carbon nanotube (CNT) or polyaniline (PANI) were prepared by in-situ polymerization of melamine and formaldehyde. Stable microcapsules were prepared and the mean diameter of the observed microcapsules was in the range of $10-20{\mu}m$. The surface morphology and chemical structure of microcapsules were investigated using optical microscope (OM), scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FT-IR). The thermal properties of samples were investigated by thermogravimetric analysis (TGA). The conductivity of ruptured microcapsule containing the suspension of CNTs or PANIs in tetrachloroethylene and Isopar-G was measured. As the amount of CNTs and PANIs in the core of microcapsules increased, the measured current increased. Conductivity measurement results suggest that poly (melamine-formaldehyde) based core-shell microcapsules could be applied to self-healing electronic materials systems, where CNTs or PANIs bridge a broken circuit upon release.

• Journal of Gifted/Talented Education
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• v.22 no.1
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• pp.141-155
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• 2012

The purpose of this study was to analyse characteristics of explanatory writing of scientifically gifted students who participated in gifted educational programs. Considering aspect of content of their explanations about cell, many of them explained the common characteristics of animal and plant cells, but a few of them did cellular characteristics of one kind of animal and plant. Some gifted students regarded cell membrane function as that of cell wall, and had a misconception that the cell was the smallest unit to consist human body. In terms of the structure of explanation, most of them didn't know the structural characteristics of explanatory writing. Finally, more than 50% of them had written using various ways to explain cell such as classifying, comparing, contrasting and exemplifying. Especially, all biologically gifted students had creatively explained drawing a picture. It was findings that the explanatory writing could be used as the instrument to evaluate knowledges of gifted students and suggested the elements of writing to teach scientific explanatory writing.

• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.344-347
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• 2011

Intrachondral articulations are the synovial joints that occur within costal cartilage in artiodactyls. The anatomical structure of Korean water deer differs from that of other deer. However, there have been no reports on the occurrence and shape of intrachondral articulations in the deer. To provide information on these articulations, we examined the occurrence and shape of intrachondral articulations in the Korean water deer by gross findings, radiography, computed tomography (CT), and histological observation. These joints often occur in the second to the tenth ribs. Morphologically, they are spheroidal joints, especially from the third to the eighth ribs, and their configuration is discernable in gross findings, radiography, CT, and histological sections. These basic results would be helpful in the diagnosis and treatment of diseases in the lateral thoracic wall of the Korean water deer.