• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.18-24
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• 1999

The satellite image acquired by RADARSAT SAR on August 15, 1996 reveals internal waves in north coastal waters of Cheju Island. It is indicated from the image data, the tidal elevation data, and the bottom topography data, the internal waves seem to be generated by interaction between shallow bottom and tidal currents travelling in the stratified water in the summer time during the tidal changeovers from ebb to flood. The internal waves generated in such condition show patterns of trains of solitons. Probable amplitude of observed solitons is calculated using estimation of the soliton wave length from SAR image data and K-dV equation. Detection of the internal waves is very significant not only to military strategist for underwater maneuvers such as operation of submarines, but also to physical and biological oceanographers. Temporal and spatial variation of the internal waves are needed to be measured by simultaneous in-situ field study together with SAR to examine the nature of these internal waves.

• Optical Science and Technology
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• v.1 no.2
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• pp.56-64
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• 1997

본 기술해설에서는 초고속 반도체 레이저의 특성을 알아보고 광통신에의 응용을 검토하였다. 먼저 반도체 레이저의 동작 원리를 설명하였고, 초고속 반도체 레이저의 소신호 및 대신호 변조특성에 대해서 기술하였다. 또한, 반도체 레이저를 이용하여 극초단 펄스를 생성하는 방법으로 이득/Q 스위칭법, 외부변조기와 집적화된 반도체 레이저를 이용하는 방법, 모드 록킹법에 대해서 검토하고 펄스 압축법에 관해서도 기술하였다. 초고속 반도체 레이저의 응용으로는 초고속 광통신, 솔리톤 광통신, 전광 시분할 다중/역다중에 관해서 기술하였다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.6
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• pp.8-18
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• 2002

We study complicated nonlinear interactions of two orthogonally polarized pulses with pulse-width of less than 100fsec in the all-optical phase-shift switches, which use soliton pulse-train and fiber-splicing for control pulse to obtain multi-collisional $\pi$-phase-shift and consider Raman response function. We investigate switching performance in various input parameters such as input pulse-width and birefringence of fiber, and find optimum initial conditions for good switching performance in such all-optical switches.

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.102-108
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• 1991

Utilizing self-phase modulation effects of a dispersion-shifted fiber and delay-line characteristics of two gratings, mode-locked 80 ps pulses at 1.319${\mu}{\textrm}{m}$ wavelength from a Nd: YAG laser are compressed down to 2.1 ps. These pulses are further compressed down to 340 fs using higher order soliton effects in a common single mode fiber.

• Proceedings of the Korea Contents Association Conference
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• 2017.05a
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• pp.185-186
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• 2017

2017년 2월 카이럴 솔리톤의 발견으로 4진법 소자가 가능해지면서 인공지능 시대의 새로운 소자로 주목받고 있다. 이는 기존의 컴퓨터 시대의 소자인 2진법의 한계를 넘어서는 것이다. 플루서의 코무니콜로기(소통학)은 소통의 철학적 담론과 체계를 제시하고 있다. 콘텐츠 프로토콜에 대한 소통학적 반성은 물리학에서 발견한 4진법의 가능성을 철학적으로 설명해줄 수 있으며, 물리학의 문제 해결에 새로운 발상을 제공해 줄 수 있다. 이는 콘텐츠 기반 연구의 학제적 연구 모델이 될 수 있다.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2441-2443
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• 1999

광섬유에서 전송되는 신호의 예측을 위하여 편미분방정식인 비선형 슈래딩거 방정식(Nonlinear Schrodinger Equation, NLSE)을 단계분할 유한 요소법(Split-Step Finite Element Method, SS-FEM)을 적용하여 해석하였다. 수치결과를 해석적인 해가 알려진 솔리톤의 해로부터 전송되는 거리의 증가에 따라 각 단계마다 오차를 계산하였으며, 그 결과를 단계분할 푸리에법(Split-Step Fourier Method, SS-FM)에 의한 수치해와도 비교하였다.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.42-43
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• 2003

The nonlinear three-wave interaction is an interesting topic having various applications in nonlinear optics, hydrodynamics, acoustic waves, and plasma physics. The resonant interaction between two laser pulses and a plasma wave plays important roles in plasma heating, laser reflection in the inertial confinement fusion (ICF), plasma wakefield generation, and ultra-intense laser pulse amplification and pulse compression using stimulated Raman backscattering (RBS). (omitted)

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.310-311
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• 2003

비선형 Kerr 매질에서 광파의 전파 특성을 해석하기 위해 지금까지 다양한 수치해석 방법들이 연구되어오고 있다 그중 FDTD 방식은 시간의 종속적인 Maxwell curl 방정식에 대해 어떠한 시간적, 공간적 근사를 사용하지 않고 광파의 전파 특성을 시뮬레이션하기 위해 유도되었기 때문에 산란과 같은 종축방향 불연속 문제나 비종축 파의 전파 특성 문제에 대해 보다 신뢰성 있는 해석 결과를 얻을 수 있으며, 비선형 Kerr 매질에서의 광파의 전파 특성에 대해서 보다 정확한 해석이 가능하다고 알려져 있다. (중략)

• Korean Journal of Optics and Photonics
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• v.18 no.2
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• pp.93-99
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• 2007

We investigated analytically and numerically the occurrence of modulation instability in fibers with periodic changes both in dispersion and gain. Previously, it has been known that the modulation instability is suppressed in dispersion managed solitons where dispersion is managed in such a way that the local dispersion alternates between the normal and the anomalous regimes. In this work, we enhanced the advantage of the dispersion management scheme by additionally introducing proper gain/loss profiles in fibers. The gain/loss profile is given by $\Gamma(z)=0.5/D(z)*(dD/dz)$, where D(z) represents the dispersion profile. The fundamental gain spectra of the modulation instability in the dispersion and gain managed fibers have been derived analytically and confirmed by numerical calculation. Our investigation reveals that in the dispersion and gain fibers the modulation instabilities are always much more suppressed compared to the case with only dispersion managed. In practical dispersion management schemes, dispersion profiles show discontinuity. and thus. the corresponding gain/loss profiles tend to be finite. In these cases, the gain/loss profiles were approximated by lumped gains/losses of finite values. Our numerical calculations confirm that this approximation also works well.

• Electrical & Electronic Materials
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• v.9 no.3
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• pp.246-250
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• 1996

In optical soliton transmission systems with nonlinear dispersive materials, which is utilized for ultra-long and high bit rate transmission, it is shown that the value of initial time difference between adjacent solitons is analyzed for optimum bit rate. The method is inducted by uncorrelation condition with minimum interaction forces in initial covariance coefficient between adjacent solitons. When the initial time difference is 6 times of soliton pulse width by the results, it is shown that the reliability is maintained with more than 90% within transmission length of soliton period. multiplied by 93.