• 제목/요약/키워드: Scattered Light

검색결과 247건 처리시간 0.024초

New Records of Marine Algae from Korea II

  • Oak, Jung-Hyun;Keum, Yeon-Shim;Hwang, Mi-Sook;Oh, Yoon-Sik
    • ALGAE
    • /
    • 제20권3호
    • /
    • pp.177-181
    • /
    • 2005
  • Two species of marine algae, Fauchea spinulosa Okamura et Segawa (Rhodymeniaceae, Rhodophyceae) and Stictyosiphon soriferus (Reinke) Rosenvinge (Chodariaceae, Phaeophyceae) were newly collected from the southern coast and Cheju Island of Korea. Fauchea spinulosa was collected from subtidal zone in the insular region of the southern coast. Plants were erect from the discoidal holdfast with short stipe, pinkish to deep red, cartilageneous, dichotomously and flabellately branched, and 10-15 cm high, 5-15 mm broad. Tetrasporangia are cruciately divided and nemathecia occurred on a side of the branches. Cystocarps were mostly coronate in marginal area and spermatangia were scattered on both sides of branches. Stictyosiphon soriferus commonly occurs on muddy and sandy intertidal flat of Namhaedo located on the southern coast. Plants are epilithic, light brown, terete, 3-5 cm high, and branched heavily in irregular or alternate manner, arising from a small holdfast with rhizoidal clumps. Plurilocular sporangia were scattered in patches and slightly swollen above the cortex of the whole filament. Unilocular sporangia were not found.

A Study on the Flow Field Characteristics of Air Induction System for Reducing the Signal-to-Noise in the MAFS Output

  • 유성출
    • 한국분무공학회지
    • /
    • 제5권1호
    • /
    • pp.49-57
    • /
    • 2000
  • This study presents the flow visualization results, velocity and turbulence intensity measurements made within an air filter cover and entry region of a mass air flow sensor (MAFS) which is used in an induction system of 3.8L engine. Flow structure in two air filter cover assemblies were examined. The first was a clear plastic replica of the production cover while the second was a modified clear plastic cover with a geometry configured to reduce fluctuations. High speed flow visualization and laser doppler velocimetry (LDV) systems were used to reveal and analyze the flow field characteristics encountered in the sensor design process under steady flow conditions. A 40-watt copper vapor laser was used as a light source. Its beam is focused down to a sheet of light approximately 1.5mm thick. The light scattered off the particles was recorded by a 16mm high speed rotating prism camera at 5000 frames per second. A comparison of the flow patterns and LDV measurements in the original and modified air filter covers is presented to illustrate the controlling effect of the cover design on the turbulence structure formation near the bypass and on the sensor output signal. In both axial and radial planes of the main passage it was found that the turbulence flow pattern is remarkably influenced by the air filter cover and main passage configuration.

  • PDF

무질서하게 분포된 산란매질에서 빔전파의 확산에 관한 검증 (Verification on Diffusion of Beam Propagation in Randomly Distributed Scattering Medium)

  • 김기준;이후설
    • 한국응용과학기술학회지
    • /
    • 제24권4호
    • /
    • pp.354-361
    • /
    • 2007
  • The distribution of light in a randomly scattering medium can represent problems found in many area. Particularly, in the clinical application of lasers for Photodynamic therapy(PDT) or in the fluorescence spectroscopy for biological tissue, turbidity plays a very important role. The influences of fluorophor, scatterer, and absorber in turbid material by light scattering were interpreted for the scattered fluorescence intensity and wavelength. The molecular properties have been studied by laser induced fluorescence spectroscopy in scattering medium as tissue. It has been found that the effects of optical properties in scattering media could be investigated by the optical $parameters({\mu}_s$, ${\mu}_a$ ,${\mu}t)$. Experimental and Monte Carlo simulation method for modelling light transport in tissue was applied. The experimental results using a randomly distributed scattering medium were discussed and compared with those obtained through Monte Carlo simulation. It'll be also important in designing the best model for oil chemistry, medicine and application of medical engineering.

광학식 입자 계수기 내 샘플 노즐 직경이 측정 효율 및 특성에 미치는 영향에 대한 실험적 연구 (Experimental analysis on effects of nozzle diameter on detection characteristics of an optical particle counter)

  • 송현우;김태욱;송순호
    • 한국입자에어로졸학회지
    • /
    • 제13권4호
    • /
    • pp.159-164
    • /
    • 2017
  • The detection efficiency and characteristics of an optical particle counter (OPC), with various sample nozzle outlet diameters, were experimentally investigated. The OPC system, which was built with original design, was made up of a diode laser, two photodetectors, and a variety of optics such as a beam splitter and a concave mirror. The cone-shaped sampling nozzle was designed to be changeable to alter the outlet diameter, within the range of 1 to 3 mm. For samples, sets of polystyrene latex (PSL) standard particle with various sizes of 1 to $3{\mu}m$, were used. As a result, detection efficiency of the OPC greatly decreased with larger nozzle outlet diameter. Moreover, increased nozzle outlet diameter means broader sample flow, thus caused light interference and multiple scattering which results in abnormal high peaks in scattered light signal. The ratio of abnormal peaks to regular signal of single particle increased with larger nozzle outlet diameter.

광산란을 이용한 연삭표면의 비접촉식 광학적 조도측정기술 (A noncontact optical roughness measurement technique of ground surface by light scattering)

  • 임동열;김승우
    • 대한기계학회논문집
    • /
    • 제12권6호
    • /
    • pp.1303-1311
    • /
    • 1988
  • 본 연구에서는 적응제어 연삭가공 공정에 사용가능한 인프로세스 표면조도 측 정기술 개발을 목표로 하여 공학을 이용한 비접촉식 조도측정 기술의 개발을 시도하였 으며 포스트 프로세스에도 사용가능 하도록 하였다. 측정기술의 개발은 정반사광과 난반사광의 단순비교 방법 (정반사광에 대한 난반사광의 비율을 이용하는 방법)과 산 란광의 패턴인식(pattern recognition)을 이용하는 방법의 두가지로 진행되었는데, 후 자의 방법에 중점이 두어 졌으며 Beckmann의 산란이론(scattering theory)이 측정시스 템 제작의 관점에서 분석되고 응용되었다.

Anti-Reflective coating for External Efficiency of Organic Light Emitting Diode

  • Kim, Byoung-Yong;Han, Jin-Woo;Kim, Jong-Yeon;Han, Jeong-Min;Moon, Hyun-Chan;Park, Kwang-Bum;Seo, Oae-Shik
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
    • /
    • pp.449-449
    • /
    • 2007
  • OLED has many advantages of low voltage operation, self radiation, light weight, thin thickness, wide view angle and fast response time to overcome existing liquid crystal display (LCD)'s weakness. Therefore, It draws attention as promising display and has already developed for manufactured goods. Also, OLED is regarded as a only substitute of flexible display with a thin display. A considerable portion of the light originating film emissive centers buried in a solid film never escapes due to internal reflection at the air-film interface and is scattered as edge emission or dissipated within the solid film This is one of the major reasons why the luminous power efficiency of OLED remains low, in spite of research progress in OLED. Although several ways of overcoming this difficulty have been reported, no comprehensive method has been proposed yet. In this paper, we propose that use of anti-reflective coating layers.

  • PDF

?레빈의 「니까」 다시 읽기 - 작가의 서사전략과 세계관을 중심으로 - (A Study of Victor Pelevin' Short Story "Nika")

  • 최행규;안병용
    • 비교문화연구
    • /
    • 제33권
    • /
    • pp.287-307
    • /
    • 2013
  • One cat caused a big wave in Russian literature. This cat revived the heroine of Russian classics. Her light breath was scattered in the world, in the cloudy sky and in the cold spring wind about one hundred years ago. And the cat gave an opportunity of turning to Russian classics to Russian readers. Thanks to this cat, a Russian dreamer changed his typical thinking, as well as many ordinary readers start to read works of creator of this wonderful cat. Pelevin accomplished these works with one cat, which he has made. Of course "Nika" is not only caused to make readers to return to Russian classics. I think, the cat and "Nika" are the symbols of writer's purpose in Russian literature. In this study the understanding of "Nika" is following the steps of realization of writer's purpose. In the second chapter it is analyzed to the textual relationship between "Nika" and "Light breath". Apart from existing analyses to be emphasized the succession of thematic aspect of two works as well. Existence of observers to each heroine stress this succession of thematic aspect of two works. In the third chapter it is analyzed the use of technique of mystification in "Nika". This intentional use of mystification has been demanded to read a "Nika" from another point of view(internal speculation of hero-narrator). The purpose of writer was to expose the cognitive error of a human being. I think this purpose was effectively explained by Pelevin's Buddhist world view which was introduced in his several works.

폐암 고에너지 방사선치료 시 갑상선 피폭에 관한 연구 (A Study on the Thyroid Dose High-Energy Radiation Therapy of Lung Cancer)

  • 양오남;임청환
    • 한국콘텐츠학회논문지
    • /
    • 제15권6호
    • /
    • pp.297-302
    • /
    • 2015
  • 고에너지 의료용 선형가속기를 이용한 폐암 방사선치료 시 갑상선에 미치는 선량을 광자극발광선량계(OSLD)를 이용하여 평가하였다. 산란광자의 영향은 3D-CRT의 경우 25.4 mSv, 28.8 mSv, 31.3 mSv, 26.5 mSv, 27.4 mSv로 5회 평균은 27.9 mSv, IMRT에 있어서는 46.8 mSv, 43.2 mSv, 42.3 mSv, 41.5 mSv, 44.1 mSv로 5회 평균은 43.6 mSv의 결과 값을 보였다. 광중성자 선량 평가 결과는 3D-CRT의 경우 3 mSv, 3 mSv, 3.4 mSv, 3.5 mSv, 3.1 mSv로 5회 평균은 3.2 mSv, IMRT에 있어서는 5.1 mSv, 4.8 mSv, 4.2 mSv, 4.8 mSv, 4.9 mSv로 5회 평균은 4.7 mSv의 결과 값을 보였다. 산란광자와 광중성자 모두 3D-CRT 보다 IMRT가 높은 것으로 평가 되었다. 본 연구를 통하여 고에너지를 이용한 방사선치료 시 인접한 정상조직에 상당한 양의 산란선량이 영향을 주는 것으로 평가된 바와 같이 방사선을 이용한 암 치료 종사자는 이러한 내용을 충분히 인지하여 피폭 저감화를 위한 노력이 필요할 것으로 사료된다.

실리콘 결정면을 이용한 LCD-BLU용 도광판의 미세산란구조 형성 (Micro-patterning of light guide panel in a LCD-BLU by using on silicon crystals)

  • 최가을;이준섭;송석호;오차환;김필수
    • 한국광학회지
    • /
    • 제16권2호
    • /
    • pp.113-120
    • /
    • 2005
  • LCD-BLU(liquid crystal device-back light unit)에 사용되는 도광판의 미세 산란패턴을 만드는 새로운 방법으로서, 실리콘 웨이퍼의 비등방 식각에 의해 자연적으로 형성되는 3차원 결정면 구조를 이용하는 방법을 제안하였다. 실리콘 3차원 결정면을 갖는 도광판과 프리즘 시트의 원판을 설계 및 제작하였고, casting 공정을 통해 PDMS 재질로 복제된 도광판을 제작하여 특성을 분석하였다. 측정 결과, 기존 인쇄형 도광판에 비해 실리콘피라미드 패턴의 도광판이 $10\%$ 증가된 정면 휘도 효율을 가질 수 있음을 실험적으로 검증하였다.

광중합기용 팁과 시판용 청광 차단 렌즈 및 노란색 착색 렌즈의 청광 투과율 비교 융합 연구 (Convergence study of blue light transmittance comparison between tips for light curing machine and commercially available blue light blocking lenses and yellow tinted lenses)

  • 이숙정
    • 한국융합학회논문지
    • /
    • 제12권7호
    • /
    • pp.125-131
    • /
    • 2021
  • 치과에서 사용횟수가 증가하고 있는 광중합형 레진 치료에는 강한 에너지를 가진 청색광이 필요하나, 그 빛은 산란 또한 커서 눈과 관련된 여러 부작용이 나타난다. 산란되는 빛에 노출되는 위험을 줄이고자 색깔 렌즈를 활용해보고자 하였다. 광중합기용 팁들과 청색광 빛의 차단에 효과가 있을 것으로 기대하는 시판용 노란색 계열의 청광 차단 렌즈와 노란색 염료로 착색한 노란색 렌즈를 UV-Vis 스펙트로미터 기기에 놓고 각각 청색광의 투과와 차단을 실험하였다. 결과로 광중합기용 팁들의 청광차단율 평균은 99.49%, 시판용 렌즈들 중 색 농도가 가장 높은 C 렌즈는 99.54%의 높은 청광차단율을 보였다. 노란색으로 착색한 렌즈의 경우에는 착색 농도가 가장 짙은 노란색 착색 C 렌즈가 87.57%의 청광차단율을 보였다. 레진 치료 시 광중합기용 팁과 함께 노란계열의 시판용 렌즈나 착색 렌즈를 착용한다면 청색광에 의한 눈과 관련된 부작용들을 줄일 수 있을 것으로 판단된다.