• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.45-54
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• 2014

This study was performed to evaluate compressive strength, flexural strength, static modulus of elasticity, stress-strain ratio and durability of abrasion on EVA concrete reinforced steel fiber (SF) in order to use hydraulic structures, underground utilities, offshore structures and structures being applied soil contaminated area. It is used ordinary portland cement, crushed coarse aggregate, nature fine aggregate, EVA redispersible polymer powder, superplasticizer and deforming agent to find optimum mix design of EVA concrete reinforced steel fiber. EVA concrete reinforced SF was effected on the improvement of mechanical properties and durability of abrasion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.93-96
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• 2005

Concrete has been considered as a semi-permanent structural material, because its excellent durability. Recently, durability decline of concrete construction by environmental pollution is becoming social problem. The durability of high durable structure is declined by carbonate, chloride permeation and deterioration of waterproof performance, etc. This study of penetrating surface protection materials evaluated about carbonation, chloride permeation, waterproof performance, and durability of abrasion, etc. It is profitable in durability that spread penetrating surface protection materials

• Magazine of the Korean Society of Agricultural Engineers
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• v.12 no.3
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• pp.2013-2018
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• 1970

Abrasion rate of coarse aggregates is an important factor to determine aggregates quality. Allowable limit of abrasion rate of coarse aggregates for concrete is 40% according to K.S. Strength and durability test of concrete with 19 efferent aggregates were made. From this test, it was found that allowable limit of abrasion rate of aggregates can be increased to 43%.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.991-996
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• 2001

The long-term durability characteristics of high-early-strength concrete were assessed. The effect of long-term durability characteristics of high-early-strength concrete were investigated. In experiment, two different types of fiber were adopted for improvement of durability. High-early-strength fiber reinforced concretes using regulated-set cements are compared with high-early-strength concrete without fiber. The durability performance of the laboratory-cured high-early-strength concrete specimens was determined by conducting an accelerated chloride permeability, abrasion resistance, freeze-thaw, surface deicer salt scaling and wet-dry repetition test. The results indicated that incorporation of fibers enhance durability performance.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.3
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• pp.55-63
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• 2011

The convex printing plate in particular securities is classified three physical properties. The main ingredient(component)of photosensitive plastic is composed of thermosetting polyamide. After being hardened specimen at $80^{\circ}C$ is shown to resist highly, the Glass Transition Temperatures of photosensitive plastic are $85^{\circ}C$. When hardened plate has reached at $80^{\circ}C$, abrasion loss is minimized. the cause is considered it is more effective in hardening when the temperature of photosensitive plastic is $80^{\circ}C$-the vitrification temperature of those. The hardness and the durability of the convex printing plate in particular securities are affected to the hardening treatment temperature. And the resolution of original drawing has being better when the durability is superior.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.3
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• pp.474-485
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• 2018

Smart sensors and connected devices have changed the concept of garments along with IT technology convergent garments that transform the performance of basic functions. Various types of products have been researched and developed due to the increased interest in smart clothing; in addition, studies based on physical and mechanical properties have also been actively studied to improve accuracy and reliability. This study represents a basic study for the development of smart textiles based on motion recognition for the surfing practice of beginners interested in IT convergence type. A physical durability evaluation of conductive yarn according to sewing method was later carried out. This study is a conditional specimen sewn with cotton lower thread and 100mm pattern length based on the results of previous studies. The durability of the conductive yarn according to the sewing method was evaluated according to the sewing method. Durability was evaluated by two kinds of repeated strain and abrasion tests. The specimen with applied cotton in a lower thread zigzag pattern 2mm stitch size 100mm stitch length was shown to have the most suitable durability for smart textile.

• The Journal of Engineering Geology
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• v.34 no.1
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• pp.67-105
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• 2024

This study compares the quartzites of four quartzite units: The Fagfog Quartzite, Dunga Quartzite (member of the Robang Formation), Pandrang Quartzite (member of the Kalitar Formation) and the Chisapani Quartzite. The analysis shows variations in flakiness and elongation, as the Fagfog Quartzite displays low flakiness whereas the Pandrang and the Chisapani have moderate and the Dunga Quartzite has shown variations. The density values of the four quartzite units remain consistent, indicating uniform physical properties and porosity levels. However, bulk density values differ among the quartzites, suggesting variations in particle arrangement, porosity, and density. Regarding strength measures, the Pandrang and the Chisapani Quartzite have higher strength characteristics as compared to the Fagfog and the Dunga Quartzites. The Pandrang Quartzite has the highest average point load strength index, classifying it as "Extremely Strong". The resistance to impact and crushing forces varies among the quartzites, with lower Aggregate Impact Value (AIV) and Aggregate Crushing Value (ACV) indicating higher strength and durability. Durability tests show that the Fagfog Quartzite has high durability against slaking, with a slight decrease observed after the fifth cycle. The Dunga Quartzite shows varying degrees of weathering, while the Pandrang and the Chisapani Quartzite have minimal weight changes, indicating strong resistance to weathering. Magnesium sulfate soundness tests indicate high durability and resistance to degradation for all four units. The Los Angeles abrasion value (LAAV) tests indicate favorable resistance to abrasion for the majority of the Fagfog, Dunga, and the Pandrang Quartzites samples, while Chisapani Quartzite shows more variability in LAAV values. The Pandrang Quartzite shows a higher proportion of elongated particles but lower flakiness index values as compared to Fagfog and Dunga Quartzites while Chisapani Quartzite stands out with a significantly higher presence of flaky particles and lower elongation index values. Mechanically, the Fagfog and Dunga Quartzite show higher strength and better resistance to abrasion and freeze and thaw. The Pandrang Quartzite shows moderate resistance to crushing and sudden effect, while the Chisapani Quartzite has variable resistance to effect. This comparative study emphasizes the diversity and complexity of quartzite rock types, showing the need for comprehensive characterization and assessment to determine their suitability for specific applications.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.537-540
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• 2003

The effects of substituting cement with fly ash(10%, 15%, 20%) and different fiber addition(polypropylene, cellulose, poly vinyl alcohol), on the control of microcrack and enhanced durability performance of face slab concrete in CFRD was studied experimentally It was conducted experiments of plastic shrinkage of mortar and concrete, and drying shrinkage of concrete. Also, durability test were carried out the chloride permeability, abrasion resistance and freeze-thaw repetition. Through the experimental results, it was concluded that ploy vinyl alcohol fiber containing concrete was the most effective mixture in control of cracking and durability.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.80-83
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• 1995

In order to develope and apply high-performance steel fiber reinforced concrete (SFRC), the effects of steel fibers on durability and long-term deformation of SFRC due to various mixing conditions have been studied. As the test result show, the manufacturing process technology of industrial SFRC is developed And the durability of SFRC such as freeze-thaw, resisteance abrasion resistance are significantly improved, the drying shrinkage of SFRC, is remarkably decreased by increasing the steel fiber contents than plain concrete

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.04a
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• pp.229-235
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• 2000

A study on the improvement of anti-abrasion nature of curved ducts for high-velocity gas-solid flow which are typically equipped in a coal-burned steam power plant has been investigated numerically and experimentally. To reduced the abrasion of pipe by particle, we have tried to form the vortex flow field in the region where flow changes its direction , modelled with two different shapes. 22.5$^{\circ}$and 90$^{\circ}$ elbows. the governing equations for three -dimensional , turbulent flow fields are discretized by FVM and solved bySIMPLE algorithm . From the numerical analysis, the new designed elbows for reducing abrasion have been developed. Numerical results are compared with the experimental abrasion data which are obtained from one of the operating coal burned steam power plants in Korea. Comparison of these results show that the developed elbows have much more durability than the original one.