• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.571-575
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• 2001

To examine the grinding effect through preheating of waste concrete as a way of retrieving coarse aggregates from waste concrete, the removal rates of cement mortar and paste of both recycled aggregates and heated and grinded ones were investigated. As the preheating temperature increased, the removal rate of cement mortar from waste concrete was raised, and this kind of removal hardly affected the abrasion rate and specific gravity of aggregates. On the other hand, when it was treated over 40$0^{\circ}C$ of preheating temperature, the absorptance was reduced to less than 2.17, and cement mortar was effectively separated from waste concrete. It could meet the Korean Standards on recycled aggregates for concrete, and it is expected to expand the scope of utilization by making it possible to retrieve the aggregates which have the properties close to natural aggregates.

• Genomics & Informatics
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• v.6 no.1
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• pp.54-58
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• 2008

Genotyping Tool for Viral SEQuences (GTVseq) provides scientists with the genotype information on the viral genome sequences including HIV-1, HIV-2, HBV, HCV, HTLV-1, HTLV-2, poliovirus, enterovirus, flavivirus, Hantavirus, and rotavirus. GTVseq produces alternative and additive genotype information for the query viral sequences based on two different, but related, scoring methods. The genotype information produced is reported in a graphical manner for the reference genotype matches and each graphical output is linked to the detailed sequence alignments between the query and the matched reference sequences. GTVseq also reports the potential 'repeats' and/or 'recombination' sequence region in a separated window. GTVseq does not replace completely other well-known genotyping tools such as NCBI's virus sequence genotyping tool (http://www.ncbi. nlm.nih.gov/projects/genotyping/formpage.cgi), but provides additional information useful in the confirmation or for further investigation of the genotype(s) for the newly isolated viral sequences.

• Journal of Korean Neurosurgical Society
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• v.63 no.4
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• pp.532-538
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• 2020

Traumatic arteriovenous fistulas (AVFs) involving the external carotid artery are exceedingly rare in young adults. Since an AVF is the most common life-threatening cause for pulsatile tinnitus (PT), meticulous evaluation and treatment of patients with PT is crucial. Here, we present two traumatic AVF cases treated with coil embolization leading to no residual fistulous connections followed by an immediate and complete resolution of PT. A 20-year-old man developed left ear tinnitus three months after a traumatic brain injury involving the right temporal bone fracture. Cerebral angiography demonstrated an enlarged left middle meningeal artery (MMA) and a fistular point at the posterior branch of the MMA draining to the middle meningeal vein (MMV) and the left pterygoid plexus, suggesting an AVF. Another 18-year-old girl developed left tinnitus, left exophthalmos, and conjunctival injection 6 months after a traffic accident involving no demonstrable abnormal findings in the radiologic exam. Magnetic resonance angiography demonstrated a markedly dilated left MMA draining to the MMV, left cavernous sinus, and left superior ophthalmic vein. In both cases, coil embolization was performed with total obliteration of the fistular point.

• Journal of Korea Foundry Society
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• v.36 no.1
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• pp.24-31
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• 2016

CD4MCU duplex stainless steel with gadolinium was fabricated as a neutron absorbing material by the air induction melting method. The gadolinium formed intermetallic compounds of Cu-Gd-Fe. There were no significant differences in hardness or ultimate tensile strength between experimental alloys. With the addition of gadolinium the yield strength of the cast alloy significantly increased, from $478.8{\pm}11.6$ to $514.2{\pm}29.9MPa$, whereas elongation of the cast alloy decreased with the addition of gadolinium, from $26.0{\pm}7.1$ to $7.0{\pm}2.5%$ due to the formation of gadolinium based intermetallic compounds.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.332-338
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• 2005

This study was conducted to prepare acrylic removable protective coatings by emulsion polymerization. Monomers used were n-butyl acrylate, acrylonitrile, butyl methacrylate. Emulsifiers used were sodium lauryl sulfate and polyoxyethylene lauryl ether, which are an anionic emulsifier and a nonionic emulsifier respectively. Potassium persulfate was used as an initiator and polyvinyl alcohol was used as a stabilizer. Emulsion polymerization was carried out in a semi-batch reactor at $70^{\circ}C$ and agitation speed was 200 rpm. Tensile strength, extension, peel strength, viscosity, and solid contents of the synthesized coatings were examined. The coatings prepared with BA:AN = 60:20 (in weight ratio) satisfied the standard for automobile in terms of extension and peel strength. When the concentration of BMA was in a range of $18{\sim}23$ wt%, the prepared coatings satisfied the standard for automobile in terms of peel strength and water resistance.

• The Korean Journal of Nuclear Medicine
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• v.38 no.1
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• pp.109-110
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• 2004

Purpose: Tc-99m MDP bone scan was performed to evaluate a generalized bone pain in a 24-year-old male chronic myelogenous leukemia patient who received bone marrow transplantation at 7 months ago. The patient had received large amounts of blood transfusion for managing symptoms related to anemia. Bone scan revealed substantial splenic tracer uptake. Magnetic resonance image and laboratory evidence of hemochromatosis suggests that the presence of large quantities of iron in the spleen of this patient may have been responsible for the splenic uptake of the bone scanning agent. The authors report a case of splenic hemochromatosis incidentally found on Tc-99m MDP bone scan.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.396-396
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• 2009

Chalcopyrite semiconductor $CuInSe_2$ nanoparticles were prepared using a low temperature colloidal route by reacting the starting materials (CuI, $InI_3$ and $Na_2Se$) in solvents. After synthesised $CuInSe_2$ nanoparticles precursors were mixed with organic binder for the viscosity of the precursor slurry to be suitable for the doctor blade method. The mixture of $CuInSe_2$ and binder was deposited onto molybdenum-coated sodalime glass substrates to form thin film. The precursor thin films were preheated on the hot plate to remove remaining solvents and binder material. After subsequent thermal processing of the thin film under a selenium ambient, $CuInSe_2$ absorber layer with grain size significantly lager than that of the nanoparticles was formed.

• Childhood Kidney Diseases
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• v.8 no.1
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• pp.86-90
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• 2004

Hemolytic uremic syndrome(HUS) is characterized by acute renal failure, microangiopathic hemolytic anemia, and thrombocytopenia and the most common pathogen is Escherichia coli (E. coli) O157 : H7. Ischemic colitis, which rarely occurs in children, is due to the reduced local blood flow to the intestine, tissue necrosis and secondary bacterial infection. We describe a patient who was admitted with abdominal pain, vomiting and hematochezia, and diagnosed as ischemic colitis by barium enema. This patient showed hemolytic anemia, thrombocytopenia and progressive renal failure and was subsequently diagnosed as hemolytic uremic syndrome. After hemodialysis, the patient showed improvement of symptoms and resolution of renal failure and ischemic colitis.

• KIEAE Journal
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• v.8 no.1
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• pp.99-104
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• 2008

This study surveys the types of form works used for constructing composite basement walls found in domestic construction sites. Based on expert surveys, the research provides criteria for selecting a form work type and cost-benefit analysis for different types of form works. In selecting a form work type, safety was considered the most important factor. It is induced from the survey that a successful construction requires a form work type that could solidly bear the lateral pressure of concrete rather than other types that cut back the cost and shorten the construction period. In the cost-benefit analysis, the benefit was the highest in 'euro-form+soldier system', and the cost was most competent in 'rib-lath+soldier system'. In considering benefit and cost together, 'euro-form+soldier system' was judged to be the best option. This is likely to be attributed to the following reasons: site workers are familiar with euro-forms because it is the most widely used; and, soldier system is more reliable in bearing lateral pressure compared to steel pipes.

• Korean Journal of Materials Research
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• v.19 no.8
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• pp.407-411
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• 2009

Reflection properties, such as specular reflection and diffuse reflection, are very important optical properties for the reflector, which has high reflectance in the display and architecture industry. Calcite is lowcost, nontoxic, and stable over a wide temperature range. Therefore, it is one of the most widely using fillers in many industries and has some advantages over titania as a filler to improve reflectance. However, optical properties, especially those of ceramic-filled composites, have not been analyzed. We studied the reflectance of calcite composites with their surface roughness. The reflectance of the composites was determined using a UV-visible spectrometer. The surface morphology and the micro-structure of the composites were investigated by atomic force microscope. The reflectance of the composites was improved by increasing the content of calcite in the calcite-frit composite. The reflectance is related with the surface roughness in the composites. However, the reflectance depends on the calcite contents in materials with similar surface roughness.