• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.513-516
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• 2006

Waste concrete powder(WCP) is a secondary by-product generated while processing waste concrete manufactured to coarse and fine aggregates for concrete. In order to assess the possibility of using WCP as admixture for self-compacting concrete, self-compactability, compressive strength and durability of self-compacting concrete containing waste concrete powder were investigated. Experimental results of this study appeared that in case of SCC mixed with WCP only, self-compactability and compressive strength decreased with increasing mixing ratio of WCP. When Blast-furnace slag(BFS) was added to SCC, self-compactability and compressive strength for a unit amount of cement increased. Also, SCC containing 15% BFS and 15%, 30% and 45% WCP, the dry shrinkage and carbonation depth appeared a tendency to decrease with increasing mixing ratio.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.210-211
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• 2014

Nowadays, as to reduce the emission volume of CO₂, blast furnace slag has been widely used to replacement of cement. Techniques about using industrial by-products has been extensively studied. For the previous study, blast furnace slag has been used with recycled fine aggregates. In thess study, considering about the different properties of blast furnace slag, as the change of blaine and chemical performances of blast furnace slag, the results of flowability and compressive strength has been analysed.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.363-368
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• 2000

This paper is an introduction of pessimum program for the identification of alkali-silica reaction of alkali-aggregate reaction which is known as one of a major factor of concrete deterioration. A series of gel-pat testing program was undertaken to observe the reactivity of potentially alkali-silica reactive concrete aggregates which were found to be reactive by previous petrographic examination (ASTM C 295). And then a pessimum program was performed in accordance with mortar-bar test method (ASTM C 227) with different percentage of those reactive components included in the fine aggregate source to determine the pessimum quantity. Chert and quartzite were found to be major components of reactive mineral/rock, and the pessimum condition for chert was about 3%, even though the test was performed with up to 25% of the component. In the case of quartzite, however, the mortar-bar expansion appeared to be directly proportional to the amount of quartzite sample with increasing tested quantity up to 35%. Both of the expansion results were well 3 and 6 month specified maximum limitation of 0.05% and of 0.1% respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.137-142
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• 1997

From the results of study on the electrical characteristics of heat-generation mortar used graphite as fine aggregates is summerized as following. The primary purpose of this study is the mixing ratio of graphite (35%, 50%/Sg), curing conditions (autoclave, steam, surface, underwater) and shape change (length, section of the electric heat-generation mortar). In case of the test condition with the steam curing condition appearance to most excellent heat-generation reproducibility. And temperature a coefficient of electric heat-generation mortar change from is in inverse proportion to the temperature a coefficient of direct proportion as the ratio of graphite mixing increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.103-104
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• 2012

Lately, minimize of the heat loss and fuel consumption when heating so that suggested ways to reduce carbon emissions as a measures to reduce for increase of carbon emission and find a way to apply highly insulated concrete as the measures. In this study, as a comparative experiments on heat conduction of concrete with lots of porous, thermal conductivity of concrete using foamed, polystyrene beads, lightweight aggregates, air-entraining agent and concrete using crushed stone measure and thermal conductivity of concrete with lots of porous compare and evaluate.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.04a
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• pp.35-40
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• 1992

Results of an experimental study on the manufacture, the workability and mechanical properties of steel fiber reinforced polyester resin composites utilizing industrial waste products are presented in this paper. The fly ash polyester resin composites using steel fiber, fly ash and calcium carbonic acid (CaCo3), unsaturated polyester resin, styrene monomer, cobalt octate and methyl ethyl ketone peroxide, fine and coarse aggregates are prepared with various filler~binder rations, binder rates and mixing conditions. As a test results, the workability of steel fiber reinforced polyester resin composites are considerably dropped with increasing fly ash-binder ratio and steel fiber volume. And compressive, flexural strength and bending toughness of the composites are remarkably improved with augmenting fiber contents.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.676-681
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• 1997

The purpose of this study is to evaluate the thermal Conductivity and Foolr Impact Sound of Polyurethane Concretes. The Polyurethane Concretes are prepared with various resin content, Fine and Coarse aggregates content, and its thickness, and tested for the Thermal Conductivity and Impact Sound. From the test results. the sound insulation grade of polyurethane concretes by the floor impact sound test on high frequency band is L-60, and its effect is considerable Polyurethane concretes have high degree of solidity compared with other heat shield materials, and its thermal conductivity is 0.05kcal/$mh^{\cire}C$. And it is suitable for sound proof floor materials.

• Computers and Concrete
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• v.16 no.3
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• pp.487-502
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• 2015

This study investigated particle expansion in basic oxygen furnace slag (BOF) and desulfurization slag (DSS) after heat curing by using the volume method. Concrete hydration was accelerated by heat curing. The compressive strength, ultrasonic pulse velocity, and resistivity of the concrete were analyzed. Maximum expansion occurred in the BOF and DSS samples containing 0.30-0.60 mm and 0.60-1.18 mm particles, respectively. Deterioration was more severe in the BOF samples. In the slag aggregates for the complete replacement of fine aggregate, severe fractures occurred in both the BOF and DSS samples. Scanning electron microscopy revealed excess CH after curing, which caused peripheral hydration products to become extruded, resulting in fracture.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.38-41
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• 2020

An 11-year-old castrated male miniature Schnauzer, weighing 8 kg, presented with multiple masses on the humeri. Grossly, the masses were separated from the surrounding soft tissues. Desmoplastic melanoma is an uncommon tumor in dogs. Fine-needle aspiration cytology showed large spindle-shaped cells with a high nuclear-cytoplasmic ratio. Histopathology showed interlacing bundles of fibroblast-like cells, highly pleomorphic multinuclear cells, occasional atypical spindle cells separated by fibrocollagenous stroma, and lymphocyte aggregates admixed with abundant collagen. The tumors were diffusely positive for S100a, a strong marker for desmoplastic melanoma, and negative for desmin. Herein, we report the pathobiology of a rare, uncommon variant of melanoma in a dog.

• Computers and Concrete
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• v.16 no.4
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• pp.545-568
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• 2015

High Performance Fiber Reinforced Cementitious Composites which are called HPFRCC, include cement matrices with strain hardening response under tension loading. In these composites, the cement mortar with fine aggregates, is reinforced by continuous or random distributed fibers and could be used for various applications including structural fuses and retrofitting of reinforced concrete members etc. In this paper, mechanical properties of HPFRCC materials are reviewed briefly. Moreover, a reinforced concrete beam (experimentally tested by Maalej et al.) is chosen and in different specimens, lower or upper or both parts of that beam are replaced with HPFRCC layers. After modeling of specimens in ABAQUS and calibration of those, mechanical properties of these specimens are investigated with different thicknesses, tensile strengths, tensile strains and compressive bars. Analytical results which are obtained by nonlinear finite analyses show that using HPFRCC layers with different parameters, increase loading capacity and ultimate displacement of these beams compare to RC specimens.