• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.191-196
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• 2009

Experiments were conducted in a constant pressure combustion chamber using schlieren system to investigate the effects of carbon dioxide/nitrogen/helium diluents on cellular instabilities of syngas-air premixed flames at room temperature and elevated pressures. Laminar burning velocities and Markstein lengths were calculated by analyzing high-speed schlieren images at various diluent concentrations and equivalence ratios. Experimental results showed substantial reduction of the laminar burning velocities and of the Markstein lengths with the diluent additions in the fuel blends. Effective Lewis numbers of helium-diluted syngas-air flames increased but those of carbon dioxide- and nitrogen-diluted syngas-air flames decreased in increase of diluents in the reactant mixtures. With helium diluent, the propensity for cells formation was significantly diminished, whereas the cellular instabilities for carbon dioxide-diluted and nitrogen-diluted syngas-air flames were not suppressed.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.145-148
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• 2005

Recently the construction of high-rise reinforced concrete building is progressively increased as the social demands. It is significantly important factors such as economy, the safety of structure, and the flexibility of internal space. Therefore new structural system is also required to be attained the reduction of story height, the flexibility and efficient use of space. The most suitable structural system is with the economy and flexibility, flat plate slab system in high-rise reinforced concrete building. In this research, it was focused in the improvement of shear performance in the flat plate system using high ductile fiber reinforced mortar. It was evaluated the shear performance in the critical region of slab-column connection. The flat plate system, designed by the high performance and safety, was developed as a new technique in the application of high-rise R/C building.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.202-205
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• 2006

Three reinforced concrete shear wall and infilled shear wall using retrofitting system were constructed and tested under both vertical and cyclic loadings, Experimental programs were carried out to evaluate and improve the seismic performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. under load reversals. All the specimens were modeled in one-third scale size. For specimens(RWAHC, RWXHC) designed by the improving of seismic performance using the high ductile fiber composite mortar, anchoring, and advanced detailing system for the reinforced concrete shear wall load-carrying capacities were increased $1.1{\sim}1.22$ times in comparison with the standard specimen(SRW).

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.329-332
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• 2006

This paper presents the experimental results for durability of an ECC designed with ground granulated blast furnace slag (BFS) through the test method of chloride ion resistance and freezing-thawing resistance. In order to compare with ECC, normal mortar was also tested. Test results showed that BFS ECC exhibited higher durability performance than ordinary mortar. These results suggest that by adding BFS in ECC, its matrix density is increased which results in decreased of deterioration and it also adds to the fiber bridging that contributes in control of cracking.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.569-570
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• 2009

An improvement of the test method is proposed to more accurately measure early-age autogenous shrinkage in concrete particularly within first 24 hours after casting. Experiments were conducted considering existing and improved method. In improved method, hydration temperature was artificially controlled to prevent thermal deformations. Test results indicate that the autogenous shrinkage calculated by existing approach is underestimated which might be due to the wrong assumption of considering the thermal dilation coefficient to be constant (equal to 10 ${\times}$ $10^{-6}/^{\circ}C$) at early-age. We recommend that the proposed method should be adopted to better assess precise value of autogenous shrinkage or an appropriate method of determining the time-evolution of thermal dilation coefficient be considered.

• Journal of Korean Public Health Nursing
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• v.28 no.2
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• pp.359-371
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• 2014

Purpose: This study was conducted in order to describe the process of appearance management with esthetic treatment and for development of a substantive theory that explains lifestyle in female college students. Methods: The participants were seven students who had undergone a surgical procedure with LASEK, cosmetic, and wearing orthodontic brackets. Data were collected through face-to-face interviews and analyzed using grounded theory in Strauss and Corbin (1998). Results: The core category, 'discovering factors of social opportunities' incorporated the relationship between and among all categories and explained the process. Theses processes were categorized acording to four stages: 'facing appearance stress', 'screening medical information', 'applying esthetic treatment', and 'restoring self-confidence'. Conclusion: The findings of this study indicate an understanding and profound insight on the issue of psycho-social health promotion in young female.

• 한국정보통신설비학회:학술대회논문집
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• 2003.08a
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• pp.204-207
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• 2003

컴퓨터화의 새로운 페러다임으로 유비쿼터스는 유비쿼터스 컴퓨팅과 유비쿼터스 네트워크를 기반으로 물리공간을 지능화함과 동시에 물리공간에 펼쳐진 각종 컨텐츠들을 네트워크로 연결시키는 노력으로 정의할 수 있다. 이러한 유비쿼터스 환경에 발맞추어 모든 물리공간에서 펼쳐진 멀티미디어 컨텐츠 역시 네트워크로 연결시키는 노력의 산물로 MPEG-21 표준화작업이 시작되었다. MPEG-21에서의 이벤트 리포팅 기술요소는 MPEG-21 내에서 발생하는 모든 이벤트 및 상호작용에 대한 표준적인 측정방법과 인터페이스를 제공한다는 점에서 그 중요성을 가진다. 본 논문에서는 멀티미디어 컨텐츠의 새로운 페러다임인 MPEG-21의 7가지 요소 중의 하나인 이벤트 리포팅에 대한 정의와 필요성에 대해 알아보고 이벤트 리포트 요구와 이벤트 리포트로 나뉘는 이벤트 리포팅의 체계를 분석한다. 또한 MPEG-21의 이벤트 리포팅에 대한 표준화 동향을 분석, 설계함으로써 이벤트 리포팅에 대한 향후 표준화 활동 방향을 제시한다.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.75-78
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• 1989

Insulation of P.E insulated cable under the field of high-voltage will be breakdown ultimately due to the degradation process called 'Treeing' which is generated in the insulation, so long as any counter-measure suppressing or eliminating it could not be provided. In this paper as a counter-measure Dodecyl Alcohol is mixed with P.E and Treeing under the temperature variation has been observed. Results show that the larger weight ratio of Dodecyl Alcohol is stronger the effect of suppressing Tree ing in the range from room temperature to 40$^{\circ}C$ and generated Treeing has been soon eliminated and it never again generated.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.209-211
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• 2001

The core in developing the transformer-operated 3 phase solid state meter is to design a single chip IC, that incorporates all the necessary features required for development of the 3 phase solid state meter. Using this technology, the solid state meter can be mass produced at lower cost and higher quality. This report deals with the performance of the prototype FPGA board, which is the final step before actual IC fabrication in fabrication LAB. All the features of FPGA board, shown in this report will be included in the final ASIC IC product.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.10
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• pp.878-882
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• 2007

Carboxylated multi-walled carbon nanotubes (MWNTs) were in detail characterized by XRD, XPS, FTIR, and thermogravimetric measurements. Carboxylic acid groups were functionalized to MWNTs under aqueous acid condition. The changes of sonication and reflux conditions rarely influenced the degree of carboxylation on MWNTs, but decreased the thermal stability of the resultant carboxylated MWNTs. XRD results showed that the diffraction peaks (100), (101), and (102) of pristine MWNTs disappeared after acid treatment, but the diffraction peak (002) was Preserved in the carboxylated MWNTs. The introduction of carboxylic acid groups on MWNTs caused to improve the dispersibility of the resultant carboxylated MWNTs in water.