• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.205-211
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• 2006

The objective of this study was to evaluate the durability of low shrinkage high performance concrete(LSHPC), which was combined with expansive additives and shrinkage reducing admixtures. We tested for not only LSHPC but also high performance concrete(HPC) and normal concrete(NC) to be compared with the durability of LSHPC. HPC was made in the same water-binder ratio of LSHPC without expansive additives and shrinkage reducing admixture. As a result, it was found that LSHPC had higher compressive and tensile strength than that of HPC. LSHPC showed more excellent performance than HPC and NC in the case of resistance to chloride ion penetration and resistance to carbonation and also showed nearly 100 durability factor in the freeze-thawing test with 500 cycles. From the examination about the watertightness and the pore distribution, it was found that the durability of LSHPC was improved because its hardened cement paste is organized closer. So we can conclude that when LSHPC is applied to structures in field, it is possible to reduce the shrinkage and crack in concrete and improve the durability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2004.05a
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• pp.105-108
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• 2004

The most of former schools facility have been planed and constructed with cement liquid waterproofing which is moth to be desired fir behavior of structure. However. It cause to decline safety for structure and also increase repairing cost that by leakage to behavior for thermal effects, Moreover, It is necessary for establishment fundamental counterplan of maintenance for schools facility to improve educational environment in budget support and proper diagnostic tech. and evaluation, repair reinforcement. In present paper, Firstly, we analyze out leakage and defect of schools facility of ㅇㅇ district office of education. Secondly, suggest the proper diagnostic tech. as leakage factor to develope efficiency of using space for durability and safety from leakage with suggestion the proper diagnostic.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.76-82
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• 2006

High-strength, High-durability concrete appearance was embossed by benevolence who quality for each raw material that become factor that is direct in concrete manufacture and the special quality is very important and request properties of matter were also strengthened more. Specially, natural resources of good quality were abundant past in occasion of aggregate and unlike concrete request strength past that the importance was less relatively the quality enemy than cement because is also not big, importance of aggregate quality great veried as concrete strength and request properties of matter about durability are strengthened more on extreme displacement. Mixing four who is original and mixs special quality examination of domestic three Four-Stick Games by Chaechwiwon and age Four-Stick Games and crushed sand examined concrete quality characteristic that use mortar and concrete quality characteristic, special quality of North Korea sun guardian mountain three Four-Stick Games that is imported from the North Korea, North Korea sun guardian mountain three Four-Stick Games etc..

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.47-53
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• 2011

Firstly, FEM model for the body frame of a fuel cell vehicle was built up and design optimization results based on different schemes were exhibited. One scheme was to minimize weight while maintaining the normal mode frequencies and the other was to increase the frequencies without weight change. Next, for a rear frame model, shape parameter study on collapse characteristics such as peak resistance load and absorbed energy was carried out. Also, the stiffness of frame mounting brackets was predicted using inertance calculation and the durability of those mounting brackets for vehicle system loads was evaluated. Finally, for a representative mounting model, the influence on durability due to thickness change was analyzed.

• Journal of Fashion Business
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• v.20 no.6
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• pp.52-65
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• 2016

Presently, sleep disorders are rapidly increasing due to sudden social development and lifestyle diversification. Among the various factors contributing to comfortable sleep, bedclothes are a major factor that readily influence the sleeping conditions, as they directly come in contact with the human body. This study therefore researches use and purchasing status of bedclothes by consumers, as well as the subjective satisfaction. This would accordingly help us to understand the consumers' performance needs, and collect basic data to develop bedclothes that assist comfortable sleep. This study used multiple choice questions and a 5-point Likert scale in a survey-style research. The results of the study indicate that consumers prudently considered practicality and durability, as bedclothes are seldom purchased. The most preferred material was cotton, but the use of microfiber, a new material, has also increased. Further, consumers' preferred lightweight bedclothes that displayed excellent water absorption, thermal insulation, durability, detergency, and flexibility. Hence, bedclothes developed according to the results of this study are expected to aid comfortable sleep.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.372-375
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• 2004

Scaling deterioration and resistance to freezing of port concrete structures due to the combined effects of chemical actions by containning chlorides and the freeze-thaw action is also a problem which has not yet been fundamentally solved. Furthermore, deterioration of concrete surface was considered as accelerate factor of concrete durability tended to decrease. Therefore, we considered the scaling measuring method and decreasing influence of durability of concrete according to kind of binders, such as OPC, Slag, Slag+Fa, due to freeze and thaw of concrete by containing chlorides. As a results of this study, it was effective method of scaling deterioration and resistance freewing of concrete, and confirmed the salt deterioration resistance effect to use slag binder against to containing chlorides.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.2
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• pp.53-59
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• 2010

Stress analysis and fatigue life on shock absorber are investigated in this study. The lower part of spring is shown with the maximum equivalent stress and displacement of 153.49MPa and 26.151mm. The rear part is also shown with the number of fatigue life less than $6.8241{\times}10^5$. And the middle part of spring is shown with the minimum safety factor of 0.94592. The designed modeling suspension in this study has no possibility with resonance. As the result of this study is applied by the chassis of automobile, the prevention on fatigue fracture and the durability is predicted.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.3
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• pp.279-284
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• 2016

Finite element analysis along with DOE scheme has been performed to obtain robust design of crankshaft assembly. This study focused on obtaining optimized fillet radius of crankshaft mainly by statistical approach. 27 design cases using 3 factors with 3 levels are constructed by design of experiment. Changes of design factors and noise factor may influence the durability of crankshaft system. General two stages of robust design may enhance the durability of crankshaft model. Increasing crank arm thickness was adopted as a shrink step and change of fillet radius was used as a shift step. By combining these two steps, the stress concentration at the fillet area is reduced and adequate fillet radius is determined for the robust design of crankshaft.

• Journal of the Korean Society for Railway
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• v.2 no.3
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• pp.61-69
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• 1999

The durability of ballast plays an important role in track behaviour. To estimate the deterioration characteristics of ballast, several tests have been carried out by several scholars. The deterioration characteristics is very important factor in the behaviour of track and its life. In this paper, abrasion/breakage characteristics of ballast is studied to see the effect of physical ballast characteristics on ballast life. To reveal breakage characteristics of ballast, the ballast box test and the MTT field test were carried out. The breakage characteristics studied in this paper is applied to the ballast life prediction in various conditions, such as LA abrasion, annual tonnage, tamping number per year, etc

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.01a
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• pp.111-113
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• 2015

This paper investigate the empirical implications. They were to verify the influences of psychological and environmental factors toward performance satisfaction and durability. The results show that actional environment on academic satisfaction in learning is the most important factor. The effect of academic satisfaction on learning durability proved to be statistically significant. The results suggest that actional environment should be considered with top priority to increase the academic satisfaction. Learning satisfaction, academic vision, and academic satisfaction to enhance students' intention to continue studies are important.