• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.54-58
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• 2003

In this study, the solution of Gel'fand-Levitan-Marchenko integral equation in the inverse scattering problem is efficiently solved for arbitrarily specified spectra pattern which are reflected from the restricted potential. The procedure is based on the successive approach without iterations. This method lessens the truncation errors which plague conventional design schemes using specific windows for reflection coefficients. It is shown that the method is adequate for the synthesis of the continuously varying one-dimensional potential of the nonuniformly distributed dielectric constants.

• 천문학회보
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• 제46권1호
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• pp.30.2-30.2
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• 2021

The extended Lyα nebulae (also known as Lyα blobs or LABs) observed at z=2-6 can provide clues to galaxy formation in the early universe. The connection of LABs with the overdensities of compact Lyα emitters suggests that they are associated with matter density peaks in the universe and thus likely to evolve into the present-day groups and clusters of galaxies. However, the mechanism powering the extended Lyα emission in LABs is remained controversial. The detection of polarization signals that follow the theoretically predicted trend is interpreted as strong evidence supporting that the LABs are caused primarily by the resonance scattering of Lyα originating from star-forming galaxies and AGNs. However, Trebitsch et al. (2016) claimed that the radial profile of polarization could be better explained by the scenario in which Lyα photons are produced in the cooling gas surrounding galaxies and then self-scattered by the gas, rather than by the scattering scenario of photons originating from the central galaxies. In this presentation, using LaRT, a state-of-art Lyα radiative transfer code, it is demonstrated that the observed polarization pattern can be reproduced even with the scattering scenario.

• 한국결정성장학회지
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• 제5권2호
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• pp.129-134
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• 1995

단결정 $KMnCl_3$, $LiNbO_3$ 및 $Mg-LiNbO_3$의 bulk 성질을 중성자 산란을 이용하여 측정하였다. 본 연구는 편광 빛을 사용하여 보이는 좋은 단결정이라도 이들의 bulk 성질을 정확히 파악하기 위하여는 중성자 산란으로 재측정하여야 함을 보여준다. 중성자 산란에서 나타나는 $KMnCl_3$, 의 큰 mosaic 분포는 이 결정이 단일 구역을 갖는 단결정이 아니고 축에 대해 작은 각으로 분포되어 있는 구역 군들이 상대적으로 여러 방향으로 존재함을 보여준다. $LiNbO_3$ 에서 나타는 작은 mosaic분포는 큰 구역들이 서로 가까이 정렬되어 있고 Mg가 첨가된 $LiNbO_3$ 는 잘 키워진 단결정으로 나타났다.

• Journal of the Optical Society of Korea
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• 제19권1호
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• pp.80-83
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• 2015

White reflective patterns are very difficult to fabricate, due to the scattering and reflection of light, especially when the pattern size goes down to micron size. A reflective white barrier structure of height $50{\mu}m$ and width $80{\mu}m$ was fabricated using dry-film resist as an intermediate reverse pattern. The reverse dry-film resist pattern was coated with an $SiO_2$ layer by sputtering, to protect the resist from chemical attack by the radical molecules in UV white resin. The UV white resin was applied on the dry-film resist pattern and then cured with ultraviolet light. The fine three-dimensional reflective patterns were finished by removing the dry-film resist.

• 수산해양기술연구
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• 제42권4호
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• pp.234-239
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• 2006

This paper introduces an auto-feeding system to exactly control the feeding time and the amount to cultured fishes in aquaculture industrial field. To reduce expensive costs or labors in this field, it was designed by the concept of controlling feed quantity exactly on the basis of fish's feeding behavior pattern in water tank. A feed control method of this system was developed for controlling feed amount by rotor capacity and motor rotated number. Moreover, a scattering section was selected by rotate way of propeller wing to scatter dried feed to designated site, and then, the diameter of its wing was 250mm and maximum scattering distance was 7.6m for 600rpm. Furthermore, the scattering ways were embodied 2 types such as a simplified way and a multistage shift way looks like a manual scattering. As a results, the multistage shift way is more effective to discharge the dried feed widely than the simple way in the water tank.

• 한국산업융합학회 논문집
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• 제25권3호
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• pp.365-378
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• 2022

Complete blood cell count(CBC) is a technique that counts leukocytes for each type of blood cell being analyzed. The principle is that laser is incident to ex vivo flowing leukocytes in a microcapillary tube and scattered light occurs by laser and leukocytes. By collecting the scattered light, we can count the types of cells because different cells generate different light-scattering patterns. However, the technique has an intrinsic limitation, scattering pattern is shown in a wide range region in the resulting, which makes it difficult to accurate analyze and use fluorescent dyes. To overcome this limitation, a new design of CBC with a dual laser, which irradiates with orthogonal angles for collecting quad-scattering information was proposed. Before development, the scattering difference depending on wavelength must be investigated to only catch up to the scattered signal by angles. Some studies, which focused on simple particles, have been conducted to theoretically and experimentally investigate different scatterings by wavelength. In this study, we propose an optical system for measuring scattered light and investigate a complex particle. As a result, the green laser made strong scattering signals in both the forward and side direction: 10% and 30%, respectively.

• 멤브레인
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• 제12권2호
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• pp.97-106
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• 2002

Polysulfone (PSf/NMP/alcohol 용액과 chlorinated poly(vinyl chloride) (CPVC)/THF/Alcohol 용액에 대한 광산란 패턴을 SALS (Small angle light scattering)와 FE-SEM (field emission scanning electron microscope)을 이용하여 조사하였다. PSf 용액에서는 시간에 따라 q값의 최대 산란 강도를 보이는 광산란 거동을 나타내어 스피노달 (SD) 상분리 거동을 나타내는 반면, CPVC 용액에서는 q값이 증가함에 따라 광산란 강도가 줄어드는 핵성장 (NG) 거동을 나타냈다. 각 고분자 용액에서 상분리 중반과 후반부에서 비용매 첨가제로 사용된 알코올의 탄소수가 증가할수록 농도분극의 증가율은 줄어들었다. 또한, SD에서의 초반부의 시간에 따른 산란 강도는 비용매 첨가제의 종류에 무관하게 Cahn의 건형 이론에 잘 부합되었다. 또한, SALS 장치로 얻어진 기공크기와 전자현미경으로 얻어진 영역 크기는 상호간에 비교되었다. 20PSf/70NMP/10n-butano1 (w/w%) 용액에 대한 산란 패턴은 초기 상분리 거동에서부터 후기 거동까지 매우 선명하게 관측되었고, 초반, 중반, 그리고 후반부에 대한 SD에 대한 이론적 결과와 잘 일치하였다. 최고의 산란강도를 나타낸 각도의 크기는 n-butanol>n-propanol>methanol>no alcohol 순으로 관찰되었으며, 이 순서로 최종 형성된 막 단면의 기공 크기가 감소되는 것으로 조사되었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.241-242
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• 2012

• 폴리머
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• 제27권4호
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• pp.313-322
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• 2003

상용화제와 교환반응 촉진제 도입에 따른 폴리(에틸렌 테레프탈레이트) (PET)/폴리(메타-자이렌 아디프아미드) (MXD-6) 블렌드의 형태구조 변화와 일축 연신한 블렌드 시료의 변형 형태구조를 조사하였다. 연신시료는 피브릴 구조의 분산상을 보여주었으며, 피브릴 구조는 연신비 증가에 따라서 점차 미세하게 변형되었다. 교환반응 촉진제나 상용화제의 첨가는 계면 접착력 향상에 기여하기보다는 분산상과 연속상 간에 결함을 야기함으로써 피브릴 구조의 균일성을 감소시켰다. H$_{v}$ 모드의 광산란을 이용하여 블렌드 조성과 연신비에 따른 고차구조 변화를 알아보았다. H$_{v}$ 산란패턴으로부터 결정들이 스택을 이루며, 스택은 연신 방향에 대하여 특정한 각도로 배향됨을 알 수 있었다. 분산상과 연속상 내의 결정은 연신비 증가에 따라서 점진적으로 배향되어, 연신비가 6.0인 경우에는 매우 높은 배향 수준을 보여주었다.

• Macromolecular Research
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• 제14권5호
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• pp.499-503
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• 2006

This report presents a new technical approach for evaluating the fiber orientation of composites using small-angle light scattering (SALS). Glass fiber (GF)/polypropylene (PP) composites with different fiber orientations were prepared by drawing compression-molded specimens. The drawn samples were remelted and then annealed at $150^{\circ}C$ in order to induce a crystalline structure on the fiber surface, and then underwent SALS analysis. The samples showed a combination of circular and streak patterns. The model calculations demonstrated that the number of nuclei on the fiber surface and the thickness of the transcrystalline layer affected the sharpness and intensity of the streak pattern. In addition, the azimuthal angle of the streak pattern was found to be dependent on the direction of the transcrystalline layer, which correlated with the fiber direction. This correlation suggests that the fiber orientation in the composites can be easily evaluated using SALS.