• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.123-130
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• 2005

The purpose of this study is to present the optimum performance of hybrid waterproofing technology, which is including material and construction method. Recently, Hybrid waterproofing technology is developed little by little in KOREA. But there is not any other criterion of performance and evaluation of this technology. So, It is needed that appropriate performance items is are settled urgently. This paper were obtained by the SPSS analysis. In this study the safety factor are more important performance of building waterproofing materials than durability comfortability and productivity. And results of this analysis showed that (1) safety performance consists of Fatigue resistance, Crack Control performance deterioration Processing of tensile performance, Compressive Strength test (2) comfortability performance consists of watertightness, bond performance (3) persistency performance consists of abrasion resistance, tensile performance, flexural strength (4) productivity performance consists of dimension, unit space weight.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.26.1-26.1
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• 2018

마그네슘 합금은 구조용 소재로 사용되는 금속 중 가장 가벼운 금속으로서 에너지 효율을 높이기 위해 경량화가 필수적으로 요구되는 자동차, 항공기, 기차 등의 운송용 기계/장비 부품으로 각광을 받고 있다. 또한 마그네슘은 생체 친화적이며 환경적 유해성이 없어서 구조소재뿐만 아니라 생체소재에 이르기까지 다양한 산업에서 유용하게 사용될 수 있는 금속이다. 그러나 현재까지도 마그네슘의 산업적 적용이 크게 증가하지 못하고 있는 이유로는 기존의 철강이나 알루미늄 소재에 비해 상대적으로 낮은 내식성, 내마모성 및 강도 문제와 높은 제품 제조 단가 등의 문제들이 있다. 특히 내식성은 대기 중에 노출되는 거의 모든 제품에서 요구되는 특성으로서 마그네슘 제품의 신뢰성을 확보함에 있어서 매우 중요하다. 현재 마그네슘 합금의 상용화를 막는 가장 큰 이유 중의 하나는 마그네슘 소재의 제조 공정비용의 경쟁력이 확보되어 있지 않기 때문이다. 본 발표에서는 마그네슘 합금의 내식성을 향상시키기 위하여 개발된 다양한 표면처리 기술들의 특성 및 효과, 그리고 공정비용의 장단점을 정리하여 발표하고자 한다.

• Journal of the Korean Applied Science and Technology
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• v.12 no.1
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• pp.19-27
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• 1995

The 2-packaged polyurethane coatings were synthesized, blending pheylmodified polyesters(of which synthetic methods were reported in the previous paper), Desmodur L-75(polyisocyanate wide1y used for coatings), wetting-dispersing agent, white pigment. etc. A variety of coating properties were tested for the coating treatment polyurethane coationgs. Compared with conventional 2-packaged polyure-thane coating, abrasion resistance and lightness index difference of the ones synthesized in the present work were somewhat decreased, but the coating properties such as hardness, gloss specular, cross hatch adhesion. etc. were improved. Especially, resistance against chemical reagents and salt were strikingly improved. In addition. the coationgs had short drying time and long pot-life. This shows that the coationgs are appropriate for rapid drying coatings.

• Elastomers and Composites
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• v.7 no.1
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• pp.45-52
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• 1972

As a series of the studies of EPDM-Polymer blends, the experiments are concentracted to the investigation of the physical properties of the EPDM-NBR blends. The results are shown as follows; 1. As EPDM addition ratio is increased, the physical properties such as resistance to ozone and aging have also improved, on the other hand, elongation and abrasion resistance decreased. 2. Tear strength is less influenced by blending and character after aging exhibited the same result. 3. Tensile strength decreased with increase in EPDM contents, especially the ratio of EPDM/NBR are 50/50 and 75/25.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.778-786
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• 2017

In this study, analyzed the changes occurred after adding casein emulsions to water - dispersed polyurethane using polypropylene glycol (PPG). For this purpose, anionic water - dispersed polyurethane containing PPG, IPDI and DMPA and casein emulsion prepared by dissolving casein in distilled water using ammonia water were prepared. As a result of measuring the alkali resistance by using the prepared resin, there was no change in the physical properties. The tensile strength of the sample having a high casein content was measured to be $2.227kgf/mm^2$. Elongation was measured at 474% for samples containing less casein and The abrasion resistance was measured as 46.090 mg.loss of sample containing much casein as a result of the surface roughness measurement.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.2
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• pp.23-30
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• 2022

After drilling, reaming is required to process a workpiece for obtaining an excellent surface quality. In general, a cermet is defined as a "composite of a ceramic hard phase and metal-bonded phase." Cermets have excellent abrasion resistance, thermal resistance, and performance in finishing operations that require surface roughness and processing precision. However, although cermets have significant advantages, research on them is insufficient. In this study, workpiece SM45C was machined using drills and cermet reamers. The cermet reamer was processed for drag finishing for 0, 4, and 6 min. The experimental results showed the effects of drag finishing on surface roughness and dimensional accuracy.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.140-141
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• 2021

Arc thermal spray process is widely used to protect the steel from corrosion and abrasion. In the present study, two different coatings i.e. Al and Al-5%Mg were used to compare their corrosion resistance performance and the effect of 5% Mg addition in the properties of deposited coating. The SEM results showed the more compact and less porous morphology of Al-5%Mg coating compared to Al. The corrosion resistance performance of both deposited coatings was studied in artificial ocean water with exposure periods and results are compared. The total impedance values of Al-5%Mg at 0.01 Hz exhibited highest with exposure periods might be attributed to the coating and corrosion products nature and morphology compared to Al coating.

• Journal of the Korean institute of surface engineering
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• v.57 no.2
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• pp.98-104
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• 2024

In order to overcome the urban heat island effect, highly functional paint is attracting attention as a promising means by shielding heat on the structure (building) surface. When a paint was prepared containing nano-sized silica particles, the heat-insulating performance was relatively higher than that of paints with other sizes. In addition, developed paints showed enhanced properties such as chemical resistance and abrasion resistance test because of the presence of nano-sized silica included in functional paint.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.3
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• pp.313-327
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• 1999

The aim of this study was to compare wear resistance of resin denture teeth opposing various restorative materials. The wear resistance of conventional acrylic resin teeth(Trubyte Biotone) and three high-strength resin teeth(Bioform IPN, Endura, SR-Orthosit-PE) opposing different restorative materials(gold alloys, dental porcelain, composite resin) was compared. Wear tests were conducted with a sliding-induced wear testing apparatus which applied 100,000 strokes to the specimen in a mesio-distal direction under conditions of 100 stroke/min and constant loading of 1Kgf/tooth. Wear resistance of the resin denture teeth was evaluated by the following criteria : 1) wear depth, 2) weight loss, and 3) SEM observation. Results were as follows. 1. When opposed to gold alloys and composite resin, high-strength resin teeth showed superior wear resistance compared to acrylic resin teeth. But, in cases opposing dental porcelain, differences between the wear of the high-strength and acrylic resin teeth were not statistically significant (p<0.05). 2. When comparing wear resistance among high-strength resin teeth, opposing gold alloys, Endura was slightly more resistant and while in cases opposing dental porcelain, SR-Orthosit-PE was showed to be slightly resistant(p<0.05). 3. The wear of high-strength resin teeth was greater by 5 to 7 times when opposing porcelain and 2 to 3 times when opposing composite resin compared to gold alloys(p<0.05). 4. SEM observations of the wear surface showed that wear of resin teeth opposing gold alloys is a fatigue type of wear and wear of resin teeth opposing dental porcelain is fatigue and abrasion type of wear. Trubyte Biotone showed more severe fatigue type of wear than high-strength resin teeth. In conclusion, the use of dental porcelain should seriously be considered as restorative material in cases opposing resin denture teeth and improvement seems to be needed on resin teeth in the areas of wear resistance.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.75-82
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• 2011

There is the uncertain period of the construction in case of the products meeting the quality standard of KS M 6080, the quality is degraded because of the abrasive loss of the paint caused by vehicle tires as the traffic amount increases and of the loss and detachment of the glass beads providing the retroreflective function. The abrupt degradation of visibility causes the high frequency of traffic accidents at night and increases the traffic accident rate. Additional supplementary construction induces the direct material and construction costs. As the more cost induction effect than the direct cost, the traffic jam caused by the additional construction increases the indirect social costs such as time cost and vehicle cost. Hence, the study is concerned with performing the abrasion resistance test based on the EN 1436 standard to check and improve the quality of various road marking materials resulting in improving the durability of road marking materials. However, even though the difference in the durability lifetime of resins(binders) is bibliographically or theoretically clear, there was no difference in the durability lifetime (retroreflectivity aspect) of the road marking paint using these binders. The reason is that the bonding of beads was very insufficient or that the cross density caused by crack or freshness was low. Moreover, the measured wet retroreflectivity was distributed as the Rw3 or higher class in average on the basis of EN 1436 but was very insufficient on the basis of the minimum wet threshold retroreflectivity with 100mcd/($m^2{\cdot}lx$) managed overseas.