• Journal of Energy Engineering
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• v.23 no.1
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• pp.1-6
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• 2014

We have surveyed on microcalorimetry which we can treat with energy dispersive spectrometer(EDS) as wavelength dispersive spectrometer(WDS), to be developed in order to make higher energy resolution as to detect X-ray peak as high as wavelength dispersive spectrometer(WDS). When we take into consideration about energy resolution, Wavelength dispersive spectrometer is 2~20eV and energy dispersive spectrometer is 140~180eV.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.466-467
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• 2007

고주파 전자계에서 플라즈마 가열을 하기 위하여 긴 파장의 펄스를 발생시키는 것이 중요한 데 마이크로파의 발진을 안정시키기 위하여 테이퍼형 지파 도파관을 연계하여 분산관계를 연구하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.5
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• pp.571-577
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• 1989

In this paper, the double-refractive index profile, which is generalized a trapezoidal index profile, is proposed to study the characteristics of a optical fiber in the wave length 1.55um. Being compared with a triangle profile, it has many advantages over an optimum core radius, the minimum refractive index difference and the change of chromati dispersion characteristics with wavelength. Though the value of a varies from 2 to infinite, the same results are approximately obtained. Therefore, in fabrication of a fiber, the step part of trapezoidal index profile can replace the profile of a-power refractive index. Because the refractive index presented in this paper varies with a, it can be applied to multiple cladding fiber or segmented core fiber. And it is expected that the characteristics of the fiber are obtained.

• The Journal of the Korea Contents Association
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• v.4 no.2
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• pp.68-75
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• 2004

In this paper, n study a distributed establishment scheme to setup lightpath in WDM/TDM Network considering user traffic characteristics. We propose a GBTA(guaranteed-bandwidth time-slot allocation) algorithm which assigns time-slots according to the requred traffic so that it can utilize given network resources efficiently in RWTA(routing and wavelength time-slot assignment) schemes. We consider traffic specification on the basis of ATM traffic classes. Also, in order to increase link utilization and minimize blocking probability, we extend distributed lightpath establishment protocol based on GBTA algorithm. In order to establish lightpath in distributed WDM/IDM network, we use backward resonation protocol that resewes resource with recent information. We use DOWTns(Distributed Optical WDM/TDM ns) that is extended from NS(Network Simulator), in order to verify proposed GBTA-based optical wavelength routed network.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.123-123
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• 2013

OCT (Optical Coherence Tomography)는 의료용 생체조직의 단층 영상을 레이저 빛을 이용하여 구현하는 첨단 의료기술이다. Time-domain과 Fourier-domain을 기반으로 다양한 광간섭 신호의 획득이 연구되고 있으며, 영상획득 속도의 향상을 위한 경쟁이 세계적으로 치열한 상황이다. 최근 초고속 파장훑음 광원(Wavelength-swept source)의 개발을 통하여 초당 300 frame 이상의 단층 영상이 구현되고 있다. 본 발표에서는 초고속 파장훑음 레이저 광원(Wavelength swept laser)이 능동형 모드잠금(Active mode locking) 외부공진 반도체 공진 구조를 기반으로 새롭게 구현된 연구 성과를 포함한다. 분산에 의한 모드 잠금에 의하여 발진 파장이 결정되어 가변하므로 1 MHz 급 이상의 초고속 반복이 가능하며, 특히 의료용 산업용 분야의 다양한 광센서 및 광영상 응용에 활발히 응용되고 있다.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.214-215
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• 2003

평면광도파로 브래그격자는 광도파로 내부의 코어의 굴절률을 주기적으로 또는 비주기적으로 변화시켜 특정 파장의 빛을 반사시키거나 투과손실로 작용하게하는 광소자이다. 이러한 광소자는 광가감다중화기, 분산보상기, 파장선택형 반사거울, 파장제거필터, 증폭기의 이득평탄화, 광스위치등 여러분야의 소자 개발의 핵심적인 기능을 부여한다. UV 엑시머레이저의 출력을 게르마늄이 첨가된 실리카 유리에 조사하여 격자구조를 형성시키는 방법이 Hill 등에 의해 발표되었고 이후, 홀로그래피 방법, 위상마스크 방법등 여러 가지의 광섬유 격자 형성방법을 활용하여 여러종류의 광통신소자들이 연구되었다. (중략)

• Analytical Science and Technology
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• v.13 no.5
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• pp.565-572
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• 2000

In this paper it was described on the standards for Xe analysis by Wavelength Dispersive X-ray Spectrometer (WDS) of Electron Probe Micro Analyser. According to the experimental results, CsI and $BaCO_3$ are appropriate compounds as standard specimen for Cs, I and Ba which has not suitable pure metal standards. In the beam current of 10-30 nA range, the Cs x-ray intensity measured from CsBr and CsI was proportional to the beam current. It was found that the linear regression factor R, showing the linearity between the atomic number and x-ray intensity between In and Nd elements, was higher than 0.99 at 25 kV and PET crystal. The caJlculated x-ray intensity of Xe standard from this linear regression equation was 1.095 times higher than that ofTe at 25 kV.

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.202-203
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• 2005

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.82-90
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• 2013

An Optical Network-on-Chip(ONoC) based on silicon photonics is one of promising technology for next generation exascale computing architectures. Recent active researches on ONoC focus on improving bandwidth further and avoiding path collisions by using wavelength division multiplexing (WDM). However, the number of wavelengths used for the WDM increases linearly as the number of Processing Element (PE) increases in existing ONoCs which adopt centralized routing architecture. The problem will also arises growing cost of optical devices such as light switches and light sources and limits the scalability of ONoC due to the sinal loss caused by interference of distinct light sources. In this paper, we proposes a distributed routing architecture for ONoC which is based on 2D-mesh structure using WDM technique and present a method that minimize the required number of wavelengths exploiting the connectivity of communication. In comparison with existing centralized routing architectures, results show reduction by 56% of the number of wavelengths and 21% of the number of optical switches in $8{\times}8$ networks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.1
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• pp.57-63
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• 1991

In this paper, propagation characteristics of W-type single mode fiber with dual shape core is investigeted theoretically. Design parameters of DSC(dual shape core) W-type single mode fiber with very low dispersion over a wide wavelength range are computed using scalar approximation. The results have larger core radius and stronger confinement for mode field distribution in core than conventional W-type fiber with single shape core.