• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.410-411
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• 2007

To investigate the ZnO LED which are interested in the next generation of short wavelength LEDs and Lasers, the ZnO thin films were deposited by RF magnetron sputtering system. The p-type ZnO thin film, fabricated by means of the ampoule-tube method, was used to make the ZnO p-n junction, and its characteristics was analyzed. The ampoule-tube method was used to make the p-type ZnO based on the As diffusion, and the hall measurement was used to confirm that the p-type is formed. the current-voltage characteristics of the ZnO p-n junction were measured to confirm the rectification characteristics of a typical p-n junction and the low leakage voltage characteristics. Analysis of ZnO LED V-I curve will provide a very useful technology for producing the UV ZnO LED and ZnO-based devices.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.3 s.94
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• pp.270-276
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• 2005

This paper presents an analytical analysis about neighboring UWB interferences in a S-DMB receiver. We first derive the C/N$_{o}$ of a S-DMB receiver, based on its specifications and present the theoretical description of its effect to UWB interferences in terms of C/(N$_{o}$+ I) and I/N$_{o}$. Using the calculated C/(N$_{o}$+ I) and I/N$_{o}$, we derive the separation distance for a S-DMB receiver not to be interfered by UWB interferences. Finally, we propose an UWB emission limit at minimum separation distance under which a S-DMB is free of UWB interferences and compare it with the value appeared in FCC proposal.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.513-516
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• 2007

Because many scientific applications require large data processing, the importance of parallel I/O has been increasingly recognized. Collective I/O is one of the considerable features of parallel I/O and enables application programmers to easily handle their large data volume. In this paper we measure and analyze the performance of original collective I/Os and the subgroup method, the way of using collective I/O of MPI effectively. From the experimental results, we found that the two kinds of subgroup method showed different performance. In terms of collective write operation, the subgroup method caused the performance degradation. However, the subgroup method for collective read showed good performance with small data size.

• Journal of the Korean Vacuum Society
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• v.16 no.1
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• pp.1-6
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• 2007

We have analyzed the atomic structure of O/Fe(100) and interface atomic structure of MgO deposited on Fe(100) surface using LEED I/V curve analysis. As the O adsorption on the Fe(100) surface, the first substrate interlayer distance is expanded by up to 16%. For 1ML MgO deposited on Fe(100) surface, the oxygen ions of MgO are located on-top of the Fe atoms, the interlayer distance at the MgO/Fe interface are expanded. From the AIA(average intensity mixing approximation) calculation, we find the interface structure of monolayer MgO on Fe(100) system has the two interface structure with MgO/FeO/Fe(100) and MgO/Fe(100). This supports the results of EELS experiment that shown existence of stretched FeO layer and coexistance of MgO/FeO/Fe(100) and MgO/Fe(100) structure.

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.11a
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• pp.113-113
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• 1993

• Textile Coloration and Finishing
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• v.14 no.4
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• pp.208-213
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• 2002

In dyeing PET/Spandex blends with disperse dyes, many disperse dyes are absorbed more readily into Spandex than PET. Inorganic/organic(I/O) values can characterize the affinity of disperse dyes for Spandex and PET fibers. As I/O values of disperse dyes approach that of Spandex, the dye uptake in Spandex increases. On the contrary, the disperse dyes of higher I/O values are absorbed more into PET than Spandex. The dye uptake in PET increases with increasing I/O values of disperse dyes. As I/O values of disperse dyes increase, the rate of dyeing become slower in the dyeing of PET/Spandex blends. Hence, the affinity and the compatibility of disperse dyes in PET/Spandex blends dyeing can be evaluated with I/O value.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06b
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• pp.460-464
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• 2010

SSD는 뛰어난 성능으로 인해 서버 시장에서 HDD를 빠르게 대체하며 각광받고 있다. 우리는 기존 SSD의 성능 분석이 단일한 I/O 패턴에 대해서만 이루어진 점을 주목하여, 다양한 패턴의 I/O가 동시에 수행 될 경우, 성능에 어떠한 영향이 있는지 평가해보고자 한다. 이를 위해 4KB부터 64MB까지 다양한 블록크기로 순차적/임의적 읽기/쓰기 연산을 수행함과 동시에 4KB 단위의 읽기/쓰기 I/O를 수행시켜 성능에 미치는 영향을 알아보았다. 이러한 평가를 네 가지 리눅스 I/O 스케줄러에 대해 각각 수행함으로써 스케줄러에 의한 영향 또한 평가하였다. 그 결과로 우리는 새로운 SSD의 성능 특성을 발견할 수 있었으며, 이는 새로운 I/O 스케줄러 및 SSD의 FTL 개발의 기반이 되리라 예상된다.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.30-32
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• 2011

현재 컴퓨터 시스템에서 대표적인 성능 저하가 발생되는 부분은 블록 I/O 시스템이다. 안드로이드와 같은 모바일 장치 또한 위와 같은 성능 이슈를 가지고 있다. 본 논문에서는 리눅스 블록 레이어의 I/O를 tracing 해주는 blktrace를 안드로이드 장치에 적용하여 SQLite를 사용하는 Web Browsing 시의 I/O 패턴 분석과 성능 개선 방안을 제시 한다.

• ETRI Journal
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• v.23 no.4
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• pp.151-157
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• 2001

Spectroscopic and thermal analysis indicates that tellurite glasses doped with $B_2O_3$ and $GeO_2$ are promising candidate host materials for wide-band erbium doped fiber amplifier (EDFA) with a high 980 nm pump efficiency. In this study, we measured the thermal stabilities and the emission cross-sections for $Er^{3+}:^{4}I_{13/2}\;{\to}\;^{4}I_{15/2}$ transition in this tellurite glass system. We also determined the Judd-Ofelt parameters and calculated the radiative transition rates and the multiphonon relaxation rates in this glass system. The 15 mol% substitution of $B_2O_3$ for $TeO_2$ in the $Er^{3+}-doped\;75TeO_2-20ZnO-5K_2O$ glass raised the multiphonon relaxation rate for $^4I_{11/2}\;{\to}\;^4I_{13/2}$ transition from 4960 $s^{-1}$ to 24700 $s^{-1}$, but shortened the lifetime of the $^4I_{13/2}$ level by 14 % and reduced the emission cross-section for the $^4I_{13/2}\;{\to}\;^4I_{15/2}$ transition by 11%. The 15 mol% $GeO_2$ substitution in the same glass system also reduced the emission cross-section but increased the lifetime by 7%. However, the multiphonon relaxation rate for $^4I_{11/2}{\to}^4I_{13/2}$ transition was raised merely by 1000 $s^{-1}$. Therefore, a mixed substitution of $B_2O_3$ and $GeO_2$ for $TeO_2$ was concluded to be suitable for the 980 nm pump efficiency and the fluorescence efficiency of $^4I_{13/2}{\to}^4I_{15/2}$ transition in $Er^{3+}-doped$ tellurite glasses.

• Journal of the Korean Institute of Rural Architecture
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• v.3 no.2
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• pp.13-24
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• 2001

Some companies of domestic construction indicate recently that modern life for the aged prefer an advanced technical alliance between O.D.L and I.D.L systems. It means the quality of housing life of the aged has been raised and changed quickly as well as the O.D.L and I.D.L systems since the last year. These preliminary studies suggest that the aged people in the country suffer from insufficient O.D.L and I.D.L systems caused by nation-wide economic poverty compared with the aged people in Seoul. The information from the country has been restricted for several decades therefore some details of the results of the studies are at times difficult to believe and differ depending on the research methods. The purpose of this study is to clarify the quality housing life of the aged, based on the comparative analysis between the O.D.L and I.D.L systems. The quality of housing life of the aged in countryside has been revealed by the clarification of the conditions housing supply, facilities, and therefore housing the cost amount. The conclusions are as follows ; The quickly changing architectural O.D.L elements are presented below in 17 items, while the I.D.L elements are presented in 18 items.